Display panel, manufacturing method thereof and display device

Abstract

The invention relates to a display panel, a manufacturing method thereof and a display device. The display panel comprises a first organic layer, a conductive layer and a second organic layer. The conductive layer is arranged on one side of the first organic layer and comprises a signal transmission part; the second organic layer is arranged on one side, away from the first organic layer, of the conductive layer; wherein an undercut opening located at the edge of the signal transmission part is formed in the first organic layer, the undercut opening and the signal transmission part are at least partially overlapped in the thickness direction of the display panel, the undercut opening is filled with the second organic layer and covers the signal transmission part, and the density of the second organic layer is different from that of the first organic layer; according to the display panel, the undercut opening in the first organic layer can be filled with the second organic layer, so that the covering condition of the second organic layer on the first organic layer and the signal transmission part is improved, the falling probability of the second organic layer is reduced, and the yield of the display panel is improved.

Description

Technical Field

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

[0002] Organic Light-Emitting Diode (OLED) display panel, also known as organic electroluminescent display panel, has broad application prospects due to its advantages of simple preparation process, low cost, low power consumption, high luminous brightness, wide operating temperature adaptability range, light and thin volume, fast response speed, easy to achieve color display and large-screen display, easy to match with integrated circuit drivers, and easy to achieve flexible display.

[0003] In an OLED display panel, a plurality of organic planar layers are often formed on an array substrate to improve the flatness of the surface of the array substrate, and a metal layer is formed between the plurality of organic planar layers to be used for signal transfer.

[0004] The metal layer is often etched with chlorine, which then needs to be replaced with oxygen to remove residual chlorine. However, oxygen will have an ashing effect on the organic flat layer below the metal layer, which can easily form an undercut structure at the edge of the metal layer. The organic flat layer above the metal layer is difficult to effectively fill the undercut structure. In subsequent processes, the gas in the undercut structure is prone to expansion, which can lead to adverse phenomena such as film shedding. Summary of the invention

[0005] The embodiments of the present application provide a display panel and a manufacturing method thereof, and a display device, which can enable the second organic layer to fill the undercut opening, reduce the probability of film layer falling off, and improve the yield rate of the display panel.

[0006] In order to achieve the above object, according to a first aspect of the present application, a display panel is provided, comprising:

[0007] A first organic layer;

[0008] A conductive layer, disposed on one side of the first organic layer, wherein the conductive layer includes a signal transmission portion;

[0009] A second organic layer is disposed on a side of the conductive layer away from the first organic layer;

[0010] Among them, the first organic layer is provided with an undercut opening located at the edge of the signal transmission part, the undercut opening and the signal transmission part at least partially overlap along the thickness direction of the display panel, the second organic layer is filled in the undercut opening and covers the signal transmission part, and the density of the second organic layer is different from the density of the first organic layer.

[0011] In one embodiment of the present application, the density of the second organic layer is greater than the density of the first organic layer.

[0012] In one embodiment of the present application, the density of the second organic layer is less than the density of the first organic layer.

[0013] In one embodiment of the present application, an elastic modulus of the second organic layer is smaller than an elastic modulus of the first organic layer.

[0014] In one embodiment of the present application, the content of hydrogen in the second organic layer is greater than the content of hydrogen in the first organic layer;

[0015] And / or, the content of oxygen in the second organic layer is greater than the content of oxygen in the first organic layer.

[0016] In an embodiment of the present application, the display panel further includes a pixel definition layer disposed on a side of the second organic layer away from the conductive layer, and a density of the first organic layer is greater than a density of the pixel definition layer.

[0017] In one embodiment of the present application, the display panel further includes:

[0018] a substrate, the first organic layer being disposed on the substrate;

[0019] A thin film transistor layer, disposed between the substrate and the first organic layer, the thin film transistor layer comprising a plurality of thin film transistors, the thin film transistor comprising an active layer, a gate, a source electrode and a drain electrode;

[0020] Wherein, the signal transmission part is connected to the source or the drain.

[0021] In one embodiment of the present application, the first organic layer has a protrusion on one side close to the signal transmission part, the orthographic projection of the protrusion on the second organic layer is located within the coverage of the orthographic projection of the signal transmission part on the second organic layer, the protrusion includes a first surface close to one side of the signal transmission part and a first side surface connected to the first surface, and the signal transmission part includes a second surface away from one side of the protrusion and a second side surface connected to the second surface;

[0022] The first side surface is retracted relative to the second side surface toward the center of the protrusion to form the undercut opening, and the second organic layer covers the first side surface and the second side surface.

[0023] In one embodiment of the present application, an angle between a portion of the first side surface close to the first surface and the first surface is less than 90°.

[0024] In one embodiment of the present application, a distance that the first side surface is retracted relative to the second side surface in a direction approaching the center of the protrusion is greater than 0 micrometers and less than or equal to 0.5 micrometers.

[0025] According to the above-mentioned purpose of the present application, an embodiment of the present application further provides a method for manufacturing a display panel, and the method for manufacturing a display panel comprises the following steps:

[0026] forming a first organic layer;

[0027] forming a conductive layer on one side of the first organic layer, wherein a signal transmission part is formed in the conductive layer;

[0028] forming an undercut opening in the first organic layer near an edge of the signal transmission portion, wherein the undercut opening at least partially overlaps with the signal transmission portion along a thickness direction of the display panel;

[0029] A second organic layer is formed on a side of the conductive layer away from the first organic layer, the second organic layer fills the undercut opening and covers the signal transmission portion, and the density of the second organic layer is different from that of the first organic layer.

[0030] In one embodiment of the present application, the step of forming the first organic layer includes:

[0031] Applying a first organic material layer and curing the layer to obtain the first organic layer;

[0032] The step of forming a second organic layer on a side of the conductive layer away from the first organic layer comprises:

[0033] A second organic material layer is coated on a side of the conductive layer away from the first organic layer, and cured to obtain the second organic layer.

[0034] In one embodiment of the present application, the coating speed of the second organic material layer is greater than 0 and less than or equal to 50 cm / min, and the distance from the spraying equipment for coating the second organic material layer to the conductive layer is greater than or equal to 100 microns and less than or equal to 130 microns.

[0035] In one embodiment of the present application, the viscosity of the second organic material layer is less than the viscosity of the first organic material layer.

[0036] According to the above-mentioned purpose of the present application, an embodiment of the present application further provides a display device, which includes the display panel.

[0037] The present application provides a display panel and a manufacturing method thereof, and a display device. By changing the properties or process parameters of the second organic layer, the density of the second organic layer is made different from the density of the first organic layer. For example, by changing the material properties or coating speed of the second organic layer, the second organic layer can fill the bottom cut opening in the first organic layer, thereby improving the coverage of the second organic layer on the first organic layer and the signal transmission part, reducing the probability of the second organic layer falling off, and improving the yield rate of the display panel.

[0038] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0040] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0041] Figure 1 A schematic diagram of the structure of a display panel provided by an embodiment;

[0042] Figure 2 A schematic diagram of the structure of the first organic layer, the conductive layer and the second organic layer provided in an embodiment of the present application;

[0043] Figure 3 A schematic diagram of the structure of a display panel provided in an embodiment of the present application;

[0044] Figure 4 Provided in the embodiments of this application Figure 2 Schematic diagram of the enlarged structure at a in the middle;

[0045] Figure 5 A flow chart of a method for manufacturing a display panel provided in an embodiment of the present application;

[0046] Figure 6 A schematic diagram of the structure of a manufacturing process of a display panel provided in an embodiment of the present application.

[0047] Description of reference numerals:

[0048] 1. First organic flat layer; 2. Metal layer; 3. Second organic flat layer; 4. Undercut structure;

[0049] 10. first organic layer; 11. protrusion; 101. undercut opening; 111. first surface; 112. first side surface;

[0050] 20. conductive layer; 21. signal transmission unit; 211. second surface; 212. second side surface;

[0051] 30. a second organic layer; 31. a second organic material layer;

[0052] 40. Substrate;

[0053] 50, thin film transistor layer; 51, thin film transistor; 511, active layer; 512, first gate; 513, second gate; 514, source; 515, drain; 52, buffer layer; 53, first gate insulating layer; 54, second gate insulating layer; 55, first interlayer dielectric layer; 56, second interlayer dielectric layer;

[0054] 61. anode; 62. pixel definition layer; 63. retaining wall;

[0055] 70. Nozzle. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0057] Please refer to Figure 1 At present, the OLED display panel includes a first organic flat layer 1, a metal layer 2 arranged on the first organic flat layer 1, and a second organic flat layer 3 arranged on the first organic flat layer 1 and covering the metal layer 2; the metal layer 2 is often patterned with chlorine, but it needs to be replaced with oxygen to remove the residual chlorine; during the oxygen replacement process, the oxygen will produce an ashing effect on the first organic flat layer 1 below the metal layer 2, and it is easy to form an undercut structure 4 at the edge of the metal layer 2, while the second organic flat layer 3 above the metal layer 2 is difficult to effectively fill the undercut structure 4. In the subsequent process, the gas in the undercut structure 4 is easy to expand, which leads to undesirable phenomena such as film shedding.

[0058] Please refer to Figure 2An embodiment of the present application provides a display panel, which includes a first organic layer 10 , a conductive layer 20 and a second organic layer 30 .

[0059] The conductive layer 20 is disposed on one side of the first organic layer 10 , and the conductive layer 20 includes a signal transmission portion 21 ; the second organic layer 30 is disposed on a side of the conductive layer 20 away from the first organic layer 10 .

[0060] Furthermore, the first organic layer 10 is provided with an undercut opening 101 located at the edge of the signal transmission portion 21, and the undercut opening 101 at least partially overlaps with the signal transmission portion 21 along the thickness direction of the display panel. The second organic layer 30 fills the undercut opening 101 and covers the signal transmission portion 21, and the density of the second organic layer 30 is different from that of the first organic layer 10.

[0061] During the implementation of the application, the embodiment of the present application changes the properties or process parameters of the second organic layer 30 so that the density of the second organic layer 30 is different from the density of the first organic layer 10. For example, the material properties or coating speed of the second organic layer 30 can be changed so that the second organic layer 30 can fill the bottom cut opening 101 in the first organic layer 10, thereby improving the coverage of the first organic layer 10 and the signal transmission part 21 by the second organic layer 30, reducing the probability of the second organic layer 30 falling off, and improving the yield rate of the display panel.

[0062] Specifically, please combine Figure 2 as well as Figure 3 The first organic layer 10 and the second organic layer 30 are two organic film layers stacked in the display panel, and the conductive layer 20 is located between the first organic layer 10 and the second organic layer 30 .

[0063] In some embodiments, the conductive layer 20 is a metal layer located between the first organic layer 10 and the second organic layer 30 , and the conductive layer 20 may include a stacked structure of Ti / Al / Ti.

[0064] In some embodiments, the display panel also includes a substrate 40 and a thin film transistor layer 50; the first organic layer 10 is disposed on the substrate 40; the thin film transistor layer 50 is disposed between the substrate 40 and the first organic layer 10, the conductive layer 20 is disposed on a side of the first organic layer 10 away from the thin film transistor layer 50 and includes the signal transmission part 21, and the second organic layer 30 is disposed on a side of the first organic layer 10 away from the thin film transistor layer 50 and covers the signal transmission part 21.

[0065] The thin film transistor layer 50 includes a plurality of thin film transistors 51 , and the thin film transistor 51 includes an active layer 511 , a gate, a source 514 , and a drain 515 ; wherein the signal transmission unit 21 is connected to the source 514 or the drain 515 .

[0066] In some embodiments, the gate includes a first gate 512 disposed on a side of the active layer 511 away from the substrate 40 and a second gate 513 disposed on a side of the first gate 512 away from the active layer 511 ; the signal transmission unit 21 is connected to the drain 515 .

[0067] In some embodiments, the thin film transistor layer 50 further includes a plurality of insulating layers covering the thin film transistor 51. Specifically, the thin film transistor layer 50 further includes a buffer layer 52 disposed on the substrate 40, the active layer 511 disposed on the buffer layer 52, a first gate insulating layer 53 disposed on the buffer layer 52 and covering the active layer 511, a first gate 512 disposed on the first gate insulating layer 53 and located on a side of the active layer 511 away from the substrate 40, a second gate insulating layer 54 disposed on the first gate insulating layer 53 and covering the first gate 512, and a second gate insulating layer 55 disposed on the second gate insulating layer 54. A second gate 513 is disposed on and located on a side of the first gate 512 away from the active layer 511, a first interlayer dielectric layer 55 is disposed on the second gate insulating layer 54 and covers the second gate 513, the source 514 and the drain 515 are disposed on the first interlayer dielectric layer 55, and a second interlayer dielectric layer 56 is disposed on the first interlayer dielectric layer 55 and covers the source 514 and the drain 515; the source 514 and the drain 515 pass through the first interlayer dielectric layer 55, the second gate insulating layer 54 and the first gate insulating layer 53 and are respectively connected to the opposite sides of the active layer 511.

[0068] In some embodiments, the display panel also includes an anode 61 disposed on a side of the second organic layer 30 away from the conductive layer 20, a pixel definition layer 62 disposed on a side of the second organic layer 30 away from the conductive layer 20, and a retaining wall 63 disposed on a side of the pixel definition layer 62 away from the second organic layer 30, a pixel opening is opened in the pixel definition layer 62, and the pixel opening corresponds to exposing a portion of the surface of the anode 61, and the anode 61 passes through the second organic layer 30 and is connected to the signal transmission unit 21.

[0069] In some embodiments, the signal transmission unit 21 can be used to transfer signals, for example, connected between the anode 61 and the drain 515 . The signal transmission unit 21 can also be a VDD signal line. In addition, the signal transmission unit 21 can also be other devices in the conductive layer 20 .

[0070] In the embodiment of the present application, the conductive layer 20 can be patterned with chlorine gas. However, after the conductive layer 20 is patterned, it is necessary to use a replacement gas to replace the surface of the conductive layer 20 and the first organic layer 10. For example, the replacement gas may include oxygen to remove residual chlorine. However, the replacement gas will have an etching effect on the first organic layer 10. In addition, the signal transmission part 21 blocks the first organic layer 10, and then an undercut opening 101 located at the edge of the signal transmission part 21 is formed in the first organic layer 10. The undercut opening 101 and the signal transmission part 21 at least partially overlap in the thickness direction of the display panel. The second organic layer 30 fills the undercut opening 101 and covers the signal transmission part 21. That is, the embodiment of the present application can improve the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21 by changing the properties or process parameters of the second organic layer 30, reduce the probability of the second organic layer 30 falling off, and improve the yield rate of the display panel.

[0071] It should be noted that the density of the second organic layer 30 can be made different from that of the first organic layer 10 by changing the material properties or coating speed of the second organic layer 30 , so that the second organic layer 30 fills the undercut opening 101 .

[0072] In some embodiments of the present application, the coating speed of the second organic layer 30 in the process can be reduced so that the material of the second organic layer 30 can better cover and fill the coating area and cover the undercut opening 101 formed in the first organic layer 10.

[0073] Among them, since the coating speed of the second organic layer 30 is slowed down, the second organic layer 30 has higher compactness and greater density after film formation; the first organic layer 10 and the second organic layer 30 belong to the same flat layer in the display panel, but in the embodiment of the present application, the coating speed of the first organic layer 10 is not changed, while the coating speed of the second organic layer 30 is reduced and can be less than the coating speed of the first organic layer 10, therefore, the density of the second organic layer 30 is greater than the density of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is greater than the elastic modulus of the first organic layer 10.

[0074] In some embodiments, the embodiments of the present application also reduce the distance from the nozzle to the coating area, which can also improve the coverage of the first organic layer 10 and the signal transmission unit 21 by the second organic layer 30 .

[0075] In some embodiments of the present application, the viscosity of the material of the second organic layer 30 may be reduced, thereby increasing the fluidity of the material of the second organic layer 30 , so that the second organic layer 30 may fill the undercut opening 101 in the first organic layer 10 .

[0076] Among them, the viscosity of the material of the second organic layer 30 is reduced, and then the density of the second organic layer 30 after film formation will be reduced, and the first organic layer 10 and the second organic layer 30 belong to the same flat layer in the display panel, but in the embodiment of the present application, the viscosity of the material of the first organic layer 10 is not changed, but the viscosity of the second organic layer 30 is reduced, and can be less than the viscosity of the first organic layer 10, therefore, the density of the second organic layer 30 is less than the density of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is less than the elastic modulus of the first organic layer 10.

[0077] In some embodiments, the process parameters of the second organic layer 30 can be changed. For example, after the material of the second organic layer 30 is coated, it will be cured into a film through a vacuum drying process. In this embodiment, the vacuum time can be reduced. As a result, when the second organic layer 30 is formed into a film, the more solvent components it contains, the lower the viscosity. The fluidity of the second organic layer 30 can be improved, making it easier for the second organic layer 30 to fill the bottom cut opening 101 in the first organic layer 10.

[0078] It should be noted that since the solvent of the second organic layer 30 is an organic solvent, it contains at least three elements: carbon, hydrogen and oxygen, for example, it can be propylene glycol methyl ether acetate; as the solvent content in the second organic layer 30 increases, the content of hydrogen and oxygen in the second organic layer 30 will also increase.

[0079] The first organic layer 10 and the second organic layer 30 are both flat layers in the display panel. However, in the embodiment of the present application, the process parameters for forming the first organic layer 10 are not changed, but the vacuuming time of the second organic layer 30 is reduced and can be less than the vacuuming time of the first organic layer 10. Therefore, the solvent content of the second organic layer 30 during film formation is greater than the solvent content of the first organic layer 10 during film formation; and further, the content of hydrogen in the second organic layer 30 is greater than the content of hydrogen in the first organic layer 10, and / or the content of oxygen in the second organic layer 30 is greater than the content of oxygen in the first organic layer 10. In addition, the density of the second organic layer 30 is less than that of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0080] It can be understood that the embodiment of the present application can improve the coverage of the first organic layer 10 and the signal transmission part 21 by the second organic layer 30 by reducing the viscosity of the material of the second organic layer 30, then the density and compactness of the second organic layer 30 are reduced, which will further reduce the water and oxygen barrier properties of the flat layer in the display panel; therefore, in the embodiment of the present application, the density of the first organic layer 10 can be increased accordingly to ensure that the water and oxygen barrier properties of the flat layer in the display panel will not be reduced, and the density of the first organic layer 10 can be greater than the density of the pixel definition layer 62.

[0081] In some embodiments, the material of the first organic layer 10 is the same as the material of the second organic layer 30 , that is, the raw material for preparing the first organic layer 10 is the same as the raw material for preparing the second organic layer 30 .

[0082] It should be noted that the first organic layer 10 has a protrusion 11 on one side close to the signal transmission part 21, and the orthographic projection of the protrusion 11 on the second organic layer 30 is located within the coverage range of the orthographic projection of the signal transmission part 21 on the second organic layer 30, wherein the protrusion 11 is formed by etching the first organic layer 10 by the replacement gas, the thickness of the etched part of the first organic layer 10 is reduced, and the protrusion 11 is formed by the part that is not etched due to the obstruction of the signal transmission part 21.

[0083] Please combine Figure 2 and Figure 4 In some embodiments, the protrusion 11 includes a first surface 111 close to the signal transmission portion 21 and a first side surface 112 connected to the first surface 111, and the signal transmission portion 21 includes a second surface 211 away from the protrusion 11 and a second side surface 212 connected to the second surface 211.

[0084] In some embodiments, the first side surface 112 is retracted relative to the second side surface 212 toward the center of the protrusion 11 to form the undercut opening 101 , and the second organic layer 30 covers the first side surface 112 and the second side surface 212 .

[0085] In some embodiments, an angle A between a portion of the first side surface 112 close to the first surface 111 and the first surface 111 is less than 90°, that is, the angle A may be an acute angle.

[0086] In some embodiments, a distance D that the first side surface 112 retracts inward relative to the second side surface 212 toward the center of the protrusion 11 is greater than 0 micrometers and less than or equal to 0.5 micrometers. For example, the distance D may be 0.1 micrometers, 0.2 micrometers, 0.3 micrometers, 0.4 micrometers or 0.5 micrometers.

[0087] The side surface of the protrusion 11 is retracted inward relative to the side surface of the signal transmission part 21 toward the center of the protrusion 11 to form the undercut opening 101, and the second organic layer 30 covers the side surface of the protrusion 11 and the side surface of the signal transmission part 21, that is, the second organic layer 30 fills the undercut opening 101 and covers the inner wall of the undercut opening 101 to completely cover the first organic layer 10 and the signal transmission part 21, thereby reducing the probability of the second organic layer 30 falling off.

[0088] Continuing from the above, the embodiment of the present application changes the properties or process parameters of the second organic layer 30 so that the density of the second organic layer 30 is different from the density of the first organic layer 10. For example, the material properties or coating speed of the second organic layer 30 can be changed so that the second organic layer 30 can fill the bottom cut opening 101 in the first organic layer 10, thereby improving the coverage of the first organic layer 10 and the signal transmission part 21 by the second organic layer 30, reducing the probability of the second organic layer 30 falling off, and improving the yield rate of the display panel.

[0089] In addition, the present application also provides a method for manufacturing a display panel. Figure 2 , Figure 3 , Figure 5 as well as Figure 6 , the manufacturing method of the display panel comprises the following steps:

[0090] S10 , forming a first organic layer 10 .

[0091] S20 , forming a conductive layer 20 on one side of the first organic layer 10 , wherein a signal transmission unit 21 is formed in the conductive layer 20 .

[0092] S30 , forming an undercut opening 101 in the first organic layer 10 near an edge of the signal transmission portion 21 , wherein the undercut opening 101 at least partially overlaps with the signal transmission portion 21 along a thickness direction of the display panel.

[0093] S40 , forming a second organic layer 30 on a side of the conductive layer 20 away from the first organic layer 10 , the second organic layer 30 filling the undercut opening 101 and covering the signal transmission portion 21 , the density of the second organic layer 30 being different from that of the first organic layer 10 .

[0094] Specifically, in step S10 , a substrate 40 is first provided.

[0095] Next, the thin film transistor layer 50 is formed on the substrate 40 . The thin film transistor layer 50 includes a plurality of thin film transistors 51 . The thin film transistor 51 includes an active layer 511 , a gate electrode, a source electrode 514 , and a drain electrode 515 .

[0096] In some embodiments, the gate includes a first gate 512 disposed on a side of the active layer 511 away from the substrate 40 and a second gate 513 disposed on a side of the first gate 512 away from the active layer 511 .

[0097] In some embodiments, the thin film transistor layer 50 further includes a plurality of insulating layers covering the thin film transistor 51. Specifically, the thin film transistor layer 50 further includes a buffer layer 52 disposed on the substrate 40, the active layer 511 disposed on the buffer layer 52, a first gate insulating layer 53 disposed on the buffer layer 52 and covering the active layer 511, a first gate 512 disposed on the first gate insulating layer 53 and located on a side of the active layer 511 away from the substrate 40, a second gate insulating layer 54 disposed on the first gate insulating layer 53 and covering the first gate 512, and a second gate insulating layer 55 disposed on the second gate insulating layer 54. A second gate 513 is disposed on and located on a side of the first gate 512 away from the active layer 511, a first interlayer dielectric layer 55 is disposed on the second gate insulating layer 54 and covers the second gate 513, the source 514 and the drain 515 are disposed on the first interlayer dielectric layer 55, and a second interlayer dielectric layer 56 is disposed on the first interlayer dielectric layer 55 and covers the source 514 and the drain 515; the source 514 and the drain 515 pass through the first interlayer dielectric layer 55, the second gate insulating layer 54 and the first gate insulating layer 53 and are respectively connected to the opposite sides of the active layer 511.

[0098] Next, the first organic layer 10 is formed on the side of the thin film transistor layer 50 away from the substrate 40 ; the first organic material layer can be coated on the side of the thin film transistor layer 50 away from the substrate 40 , and the first organic material layer can be cured to obtain the first organic layer 10 .

[0099] In step S20 , a conductive material layer is formed on a side of the first organic layer 10 away from the thin film transistor layer 50 . The conductive material layer may include a stacked structure of Ti / Al / Ti.

[0100] Next, the conductive material layer is patterned to form the conductive layer 20 , and the signal transmission portion 21 is formed in the conductive layer 20 .

[0101] For example, chlorine gas may be used to perform dry etching on the conductive material layer. However, during etching, chlorine gas or chlorine element may remain on the surface of the film layer, which may damage the film layer and affect subsequent processes.

[0102] In step S30, since there may be residual chlorine gas or chlorine element on the surface of the film layer, which may damage the film layer and affect subsequent processes, the embodiment of the present application may use a replacement gas to replace the surface of the first organic layer 10 and the conductive layer 20 to remove the residual chlorine gas or chlorine element. For example, the replacement gas may include oxygen.

[0103] The replacement gas will produce an etching effect on the first organic layer 10, and due to the shielding effect of the signal transmission part 21 on the first organic layer 10, when the replacement gas etches the first organic layer 10 in the vertical direction, it will also produce horizontal etching at the edge of the signal transmission part 21, so that the first organic layer 10 forms the undercut opening 101 at the edge of the signal transmission part 21, and the replacement gas will move the first organic layer 10 located at the edge of the signal transmission part 21 toward the bottom of the signal transmission part 21, so that the undercut opening 101 at least partially overlaps with the signal transmission part 21 along the thickness direction of the display panel.

[0104] In step S40 , a second organic material layer 31 is coated on a side of the conductive layer 20 away from the first organic layer 10 , and cured to obtain the second organic layer 30 , and the second organic layer 30 fills the undercut opening 101 and covers the signal transmission portion 21 .

[0105] In the embodiment of the present application, the material properties or coating speed of the second organic layer 30 can be changed so that the second organic layer 30 can fill the undercut opening 101 in the first organic layer 10, thereby improving the coverage of the first organic layer 10 and the signal transmission part 21 by the second organic layer 30, reducing the probability of the second organic layer 30 falling off, and improving the yield rate of the display panel.

[0106] In some embodiments of the present application, the coating speed of the second organic layer 30 in the process can be reduced and the distance from the nozzle to the coating area can be reduced so that the material of the second organic layer 30 can better cover and fill the coating area and cover the undercut opening 101 formed in the first organic layer 10.

[0107] In some embodiments, the coating speed of the second organic material layer 31 is greater than 0 and less than or equal to 50 cm / min, and the distance from the spraying equipment for coating the second organic material layer 31 to the conductive layer 20 is greater than or equal to 100 μm and less than or equal to 130 μm.

[0108] In the embodiment of the present application, the process parameters of the second organic layer 30 are adjusted to verify the coverage of the first organic layer 10 by the second organic layer 30 .

[0109] As shown in Table 1 below, the parameters and process conditions of the second organic layer 30 in Comparative Examples 1 to 3, and Examples 1 and 2 provided in the embodiments of the present application are shown.

[0110] like Figure 6 As shown, in Comparative Examples 1 to 3, as well as Examples 1 and 2, the following can be used: Figure 6 The second organic material layer 31 is coated by the spraying structure shown, and then cured to form a film, so as to obtain the second organic layer 30.

[0111] Table 1

[0112]

[0113] In comparative example 1, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H between the nozzle 70 and the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 70 cm / min.

[0114] In Comparative Example 2, the film thickness of the second organic layer 30 is 2 micrometers, the distance H between the nozzle 70 and the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 70 cm / min.

[0115] In Comparative Example 3, the film thickness of the second organic layer 30 is 2.7 micrometers, the distance H between the nozzle 70 and the conductive layer 20 is 130 micrometers, and the coating speed of the nozzle 70 is 70 cm / min.

[0116] In Example 1, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H between the nozzle 70 and the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 50 cm / min.

[0117] In Example 2, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H between the nozzle 70 and the conductive layer 20 is 130 micrometers, and the coating speed of the nozzle 70 is 50 cm / min.

[0118] It can be seen from Table 1 that Example 1 and Example 2 can fill the undercut opening 101 in the first organic layer 10, while Comparative Examples 1 to 3 cannot fill the undercut opening 101; therefore, it can be shown that the embodiments of the present application can effectively improve the coverage of the first organic layer 10 by the second organic layer 30 and reduce the probability of the second organic layer 30 falling off by reducing the coating speed of the second organic material layer 31.

[0119] Furthermore, since the coating speed of the second organic layer 30 is slowed down, the second organic layer 30 has higher compactness and density after film formation; the first organic layer 10 and the second organic layer 30 belong to the same flat layer in the display panel, but in the embodiment of the present application, the coating speed of the first organic layer 10 is not changed, while the coating speed of the second organic layer 30 is reduced and can be less than the coating speed of the first organic layer 10. Therefore, the density of the second organic layer 30 is greater than that of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is greater than that of the first organic layer 10.

[0120] In some embodiments of the present application, the viscosity of the second organic material layer 31 may be reduced, thereby increasing the fluidity of the second organic material layer 31 , so that the second organic layer 30 may fill the undercut opening 101 in the first organic layer 10 .

[0121] Among them, the viscosity of the second organic material layer 31 is reduced, and then the density of the second organic layer 30 after film formation will be reduced, and the first organic layer 10 and the second organic layer 30 belong to the same flat layer in the display panel, but in the embodiment of the present application, the viscosity of the first organic material layer is not changed, but the viscosity of the second organic material layer 31 is reduced, and can be less than the viscosity of the first organic material layer. Therefore, the density of the second organic layer 30 is less than the density of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is less than the elastic modulus of the first organic layer 10.

[0122] In some embodiments, the process parameters of the second organic material layer 31 can be changed. For example, after the second organic material layer 31 is coated, it will be cured into a film through a vacuum drying process. In this embodiment, the vacuum drying time can be reduced. As a result, when the second organic material layer 31 is formed into a film, the more solvent components it contains, the lower the viscosity. The fluidity of the second organic material layer 31 can be improved, making it easier for the second organic material layer 31 to fill the bottom cut opening 101 in the first organic layer 10.

[0123] It should be noted that since the solvent of the second organic material layer 31 is an organic solvent, it contains at least three elements of carbon, hydrogen and oxygen, for example, it can be propylene glycol methyl ether acetate; since the solvent content in the second organic layer 30 after film formation increases, the content of hydrogen and oxygen elements in the second organic layer 30 will also increase.

[0124] The first organic layer 10 and the second organic layer 30 are both flat layers in the display panel. However, in the embodiment of the present application, the process parameters for forming the first organic layer 10 are not changed, but the vacuuming time of the second organic layer 30 is reduced and can be less than the vacuuming time of the first organic layer 10. Therefore, the solvent content of the second organic layer 30 during film formation is greater than the solvent content of the first organic layer 10 during film formation; and further, the content of hydrogen in the second organic layer 30 is greater than the content of hydrogen in the first organic layer 10, and / or the content of oxygen in the second organic layer 30 is greater than the content of oxygen in the first organic layer 10. In addition, the density of the second organic layer 30 is less than that of the first organic layer 10; further, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0125] It can be understood that the embodiment of the present application can improve the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21 by reducing the viscosity of the second organic material layer 31, then the density and compactness of the second organic layer 30 are reduced, which will further reduce the water and oxygen barrier properties of the flat layer in the display panel; therefore, in the embodiment of the present application, the density of the first organic layer 10 can be increased accordingly to ensure that the water and oxygen barrier properties of the flat layer in the display panel will not be reduced, and the density of the first organic layer 10 can be greater than the density of the pixel definition layer 62.

[0126] In some embodiments, the material of the first organic layer 10 is the same as the material of the second organic layer 30 , that is, the raw material for preparing the first organic layer 10 is the same as the raw material for preparing the second organic layer 30 .

[0127] In summary, the embodiments of the present application change the properties or process parameters of the second organic layer 30 so that the density of the second organic layer 30 is different from that of the first organic layer 10. For example, the material properties or coating speed of the second organic layer 30 can be changed so that the second organic layer 30 can fill the bottom cut opening 101 in the first organic layer 10, thereby improving the coverage of the first organic layer 10 and the signal transmission part 21 by the second organic layer 30, reducing the probability of the second organic layer 30 falling off, and improving the yield rate of the display panel.

[0128] In addition, an embodiment of the present application further provides a display device, which includes the display panel described in the above embodiment.

[0129] It can be understood that, since the display device includes the display panel described in the above embodiment, the display device has the same beneficial effects as in the above embodiment, which will not be described in detail herein.

[0130] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0131] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0132] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0133] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A display panel, characterized in that: include: A first organic layer; A conductive layer, disposed on one side of the first organic layer, the conductive layer comprising a signal transmission portion; A second organic layer is disposed on a side of the conductive layer away from the first organic layer; Among them, the first organic layer is provided with an undercut opening located at the edge of the signal transmission part, the undercut opening and the signal transmission part at least partially overlap along the thickness direction of the display panel, the second organic layer is filled in the undercut opening and covers the signal transmission part, and the density of the second organic layer is different from the density of the first organic layer.

2. The display panel according to claim 1, characterized in that: The density of the second organic layer is greater than the density of the first organic layer.

3. The display panel according to claim 1, characterized in that: The density of the second organic layer is lower than the density of the first organic layer.

4. The display panel according to claim 3, characterized in that: An elastic modulus of the second organic layer is smaller than an elastic modulus of the first organic layer.

5. The display panel according to claim 3, characterized in that: The content of hydrogen in the second organic layer is greater than the content of hydrogen in the first organic layer; And / or, the content of oxygen in the second organic layer is greater than the content of oxygen in the first organic layer.

6. The display panel according to claim 3, characterized in that: The display panel further includes a pixel definition layer disposed on a side of the second organic layer away from the conductive layer, and a density of the first organic layer is greater than a density of the pixel definition layer.

7. The display panel according to claim 1, characterized in that: The display panel further includes: a substrate, the first organic layer being disposed on the substrate; A thin film transistor layer, disposed between the substrate and the first organic layer, the thin film transistor layer comprising a plurality of thin film transistors, the thin film transistor comprising an active layer, a gate, a source electrode and a drain electrode; Wherein, the signal transmission part is connected to the source or the drain.

8. The display panel according to any one of claims 1 to 7, characterized in that: The first organic layer has a protrusion on one side close to the signal transmission part, the orthographic projection of the protrusion on the second organic layer is located within the coverage of the orthographic projection of the signal transmission part on the second organic layer, the protrusion includes a first surface close to the signal transmission part and a first side surface connected to the first surface, and the signal transmission part includes a second surface away from the protrusion and a second side surface connected to the second surface; The first side surface is retracted relative to the second side surface toward the center of the protrusion to form the undercut opening, and the second organic layer covers the first side surface and the second side surface.

9. The display panel according to claim 8, characterized in that: An angle between a portion of the first side surface close to the first surface and the first surface is less than 90°.

10. The display panel according to claim 8, characterized in that: The distance that the first side surface shrinks inward relative to the second side surface toward the center of the protrusion is greater than 0 micrometers and less than or equal to 0.5 micrometers.

11. A method for manufacturing a display panel, characterized in that: The manufacturing method of the display panel comprises the following steps: forming a first organic layer; forming a conductive layer on one side of the first organic layer, wherein a signal transmission part is formed in the conductive layer; forming an undercut opening in the first organic layer near an edge of the signal transmission portion, wherein the undercut opening at least partially overlaps with the signal transmission portion along a thickness direction of the display panel; A second organic layer is formed on a side of the conductive layer away from the first organic layer, the second organic layer fills the undercut opening and covers the signal transmission portion, and the density of the second organic layer is different from that of the first organic layer.

12. The method for manufacturing a display panel according to claim 11, characterized in that: The step of forming the first organic layer comprises: Applying a first organic material layer and curing the layer to obtain the first organic layer; The step of forming a second organic layer on a side of the conductive layer away from the first organic layer comprises: A second organic material layer is coated on a side of the conductive layer away from the first organic layer, and cured to obtain the second organic layer.

13. The method for manufacturing a display panel according to claim 12, characterized in that: The coating speed of the second organic material layer is greater than 0 and less than or equal to 50 cm / min, and the distance from the spraying equipment coating the second organic material layer to the conductive layer is greater than or equal to 100 microns and less than or equal to 130 microns.

14. The method for manufacturing a display panel according to claim 12, wherein: The viscosity of the second organic material layer is lower than that of the first organic material layer.

15. A display device, characterized in that: The display device comprises the display panel according to any one of claims 1 to 10.

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