Display panel and manufacturing method therefor, and display apparatus

Abstract

The present application relates to a display panel and a manufacturing method therefor, and a display apparatus. A first organic layer is provided with undercut openings at an edge of a signal transmission portion, wherein the undercut openings at least partially overlap the signal transmission portion in a thickness direction of the display panel, a second organic layer fills the undercut openings and covers the signal transmission portion, and the density of the second organic layer is different from that of the first organic layer.

Description

Display panel and its manufacturing method, display device Technical Field

[0001] This application relates to the field of display technology, and in particular to a display panel, a method for manufacturing the same, and a display device. Background Technology

[0002] Organic light-emitting diode (OLED) display panels, also known as organic electroluminescent display panels, have broad application prospects due to their advantages such as simple manufacturing process, low cost, low power consumption, high brightness, wide operating temperature range, thin and light size, fast response speed, ease of achieving color and large-screen displays, ease of matching with integrated circuit drivers, and ease of achieving flexible displays.

[0003] In OLED display panels, multiple organic planarization layers are often formed on the array substrate to improve the flatness of the array substrate surface, and metal layers are formed between the multiple organic planarization layers, which can be used to transfer signals.

[0004] The metal layer is often etched with chlorine gas, and then replaced with oxygen to remove the residual chlorine gas. However, oxygen can cause ashing of the organic planarization layer under the metal layer, which can easily form undercut structures at the edge of the metal layer. The organic planarization layer above the metal layer is difficult to effectively fill the undercut structures. In subsequent processes, the gas in the undercut structures is prone to expansion, which can lead to defects such as film peeling. Invention Overview

[0005] This application provides a display panel and its manufacturing method and display device, which can make the second organic layer fill the undercut opening, reduce the probability of film layer peeling off, and improve the yield of the display panel.

[0006] To achieve the above objectives, according to a first aspect of this application, a display panel is provided, comprising:

[0007] First organic layer;

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

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

[0010] The first organic layer has an undercut opening located at the edge of the signal transmission section. The undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer.

[0011] In accordance with the above-mentioned objectives of this application, embodiments of this application also provide a method for manufacturing a display panel, the method comprising the following steps:

[0012] Formation of the first organic layer;

[0013] A conductive layer is formed on one side of the first organic layer, and a signal transmission section is formed in the conductive layer;

[0014] An undercut opening is formed in the first organic layer near the edge of the signal transmission section, and the undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel;

[0015] A second organic layer is formed on the side of the conductive layer away from the first organic layer. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer.

[0016] In accordance with the above-mentioned objectives of this application, embodiments of this application also provide a display device, the display device including a display panel, the display panel comprising:

[0017] First organic layer;

[0018] A conductive layer is disposed on one side of the first organic layer, and the conductive layer includes a signal transmission section;

[0019] The second organic layer is disposed on the side of the conductive layer away from the first organic layer;

[0020] The first organic layer has an undercut opening located at the edge of the signal transmission section. The undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0023] Figure 1 is a schematic diagram of the structure of a display panel provided in one embodiment;

[0024] Figure 2 is a schematic diagram of a structure of a first organic layer, a conductive layer, and a second organic layer provided in an embodiment of this application.

[0025] Figure 3 is a schematic diagram of a display panel provided in an embodiment of this application;

[0026] Figure 4 is an enlarged structural schematic diagram of point a in Figure 2 provided in an embodiment of this application;

[0027] Figure 5 is a flowchart of the manufacturing method of the display panel provided in the embodiment of this application;

[0028] Figure 6 is a schematic diagram of the manufacturing process of a display panel provided in an embodiment of this application.

[0029] Explanation of reference numerals in the attached figures:

[0030] 1. First organic planarization layer; 2. Metal layer; 3. Second organic planarization layer; 4. Undercut structure;

[0031] 10. First organic layer; 11. Protrusion; 101. Undercut opening; 111. First surface; 112. First side surface;

[0032] 20. Conductive layer; 21. Signal transmission section; 211. Second surface; 212. Second side surface;

[0033] 30. Second organic layer; 31. Second organic material layer;

[0034] 40. Substrate;

[0035] 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;

[0036] 61. Anode; 62. Pixel definition layer; 63. Barrier;

[0037] 70. Nozzle. Embodiments of the present invention

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0039] Referring to Figure 1, currently, an OLED display panel includes a first organic planarization layer 1, a metal layer 2 disposed on the first organic planarization layer 1, and a second organic planarization layer 3 disposed on the first organic planarization layer 1 and covering the metal layer 2. The metal layer 2 is often patterned using chlorine gas, but it needs to be replaced with oxygen to remove residual chlorine gas. During the oxygen replacement process, oxygen will ashing effect on the first organic planarization layer 1 below the metal layer 2, which easily forms an undercut structure 4 at the edge of the metal layer 2. The second organic planarization layer 3 above the metal layer 2 is difficult to effectively fill the undercut structure 4. In subsequent processes, the gas in the undercut structure 4 is prone to expansion, which can lead to defects such as film peeling.

[0040] Referring to Figure 2, this application embodiment provides a display panel, which includes a first organic layer 10, a conductive layer 20, and a second organic layer 30.

[0041] The conductive layer 20 is disposed on one side of the first organic layer 10, and the conductive layer 20 includes a signal transmission part 21; the second organic layer 30 is disposed on the side of the conductive layer 20 away from the first organic layer 10.

[0042] Furthermore, the first organic layer 10 has an undercut opening 101 located at the edge of the signal transmission section 21. The undercut opening 101 at least partially overlaps with the signal transmission section 21 along the thickness direction of the display panel. The second organic layer 30 fills the undercut opening 101 and covers the signal transmission section 21. The density of the second organic layer 30 is different from the density of the first organic layer 10.

[0043] In the implementation process, the embodiments of this 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 undercut opening 101 in the first organic layer 10, thereby improving the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21, reducing the probability of the second organic layer 30 falling off, and improving the yield of the display panel.

[0044] In one embodiment of this application, the density of the second organic layer is greater than the density of the first organic layer.

[0045] In one embodiment of this application, the density of the second organic layer is less than the density of the first organic layer.

[0046] In one embodiment of this application, the elastic modulus of the second organic layer is less than that of the first organic layer.

[0047] In one embodiment of this application, the hydrogen content in the second organic layer is greater than the hydrogen content in the first organic layer;

[0048] And / or, the oxygen content in the second organic layer is greater than the oxygen content in the first organic layer.

[0049] In one embodiment of this application, the display panel further includes a pixel definition layer disposed on the side of the second organic layer away from the conductive layer, wherein the density of the first organic layer is greater than the density of the pixel definition layer.

[0050] In one embodiment of this application, the display panel further includes:

[0051] A substrate, wherein the first organic layer is disposed on the substrate;

[0052] A thin-film transistor layer is disposed between the substrate and the first organic layer. The thin-film transistor layer includes a plurality of thin-film transistors, and each thin-film transistor includes an active layer, a gate, a source, and a drain.

[0053] The signal transmission unit is connected to either the source or the drain.

[0054] In one embodiment of this application, the first organic layer has a protrusion on the side near the signal transmission part, and the orthographic projection of the protrusion on the second organic layer is located within the coverage area of ​​the orthographic projection of the signal transmission part on the second organic layer. The protrusion includes a first surface near 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.

[0055] The first side is recessed inward relative to the second side in a direction close to the center of the protrusion to form the undercut opening, and the second organic layer covers the first side and the second side.

[0056] In one embodiment of this application, the angle between the portion of the first side closest to the first surface and the first surface is less than 90°.

[0057] In one embodiment of this application, the first side is recessed inward relative to the second side in the direction closer to the center of the protrusion by a distance greater than 0 micrometers and less than or equal to 0.5 micrometers.

[0058] Specifically, referring to Figures 2 and 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.

[0059] 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 Ti / Al / Ti stacked structure.

[0060] In some embodiments, the display panel further 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 the side of the first organic layer 10 away from the thin-film transistor layer 50 and includes the signal transmission portion 21; the second organic layer 30 is disposed on the side of the first organic layer 10 away from the thin-film transistor layer 50 and covers the signal transmission portion 21.

[0061] The thin-film transistor layer 50 includes a plurality of thin-film transistors 51, each thin-film transistor 51 including 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.

[0062] In some embodiments, the gate includes a first gate 512 disposed on the side of the active layer 511 away from the substrate 40 and a second gate 513 disposed on the side of the first gate 512 away from the active layer 511; the signal transmission section 21 is connected to the drain 515.

[0063] 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, an 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 the 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 54 disposed on the second gate insulating layer 54. The first gate 512 is located on the side away from the active layer 511, and a second gate 513 is disposed on the second gate insulating layer 54 and covers the second gate 513. A source 514 and a 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.

[0064] In some embodiments, the display panel further includes an anode 61 disposed on the side of the second organic layer 30 away from the conductive layer 20, a pixel definition layer 62 disposed on the side of the second organic layer 30 away from the conductive layer 20, and a barrier 63 disposed on the side of the pixel definition layer 62 away from the second organic layer 30. The pixel definition layer 62 has a pixel opening, and the pixel opening exposes a portion of the surface of the anode 61. The anode 61 passes through the second organic layer 30 and is connected to the signal transmission unit 21.

[0065] In some embodiments, the signal transmission unit 21 can be used to transfer signals, for example, by connecting 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.

[0066] In this embodiment, the conductive layer 20 can be patterned using chlorine gas. However, after patterning the conductive layer 20, a displacement gas is needed to replace the surface of the conductive layer 20 and the first organic layer 10. For example, the displacement gas may include oxygen to remove residual chlorine. However, the displacement gas will etch the first organic layer 10. In addition, the signal transmission part 21 will block the first organic layer 10, resulting in an undercut opening 101 at the edge of the signal transmission part 21 in the first organic layer 10. The undercut opening 101 and the signal transmission part 21 at least partially overlap along 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, this embodiment 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 of the display panel.

[0067] 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.

[0068] In some embodiments of this application, the coating speed of the second organic layer 30 during 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.

[0069] In this embodiment, because the coating speed of the second organic layer 30 is slowed down, the second organic layer 30 has higher density and greater compactness after film formation. The first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel. However, in this embodiment, the coating speed of the first organic layer 10 is not changed, but 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. Furthermore, the elastic modulus of the second organic layer 30 is greater than the elastic modulus of the first organic layer 10.

[0070] In some embodiments, the distance from the nozzle to the coating area is also reduced, which can also improve the coverage of the second organic layer 30 over the first organic layer 10 and the signal transmission unit 21.

[0071] In some embodiments of this application, the fluidity of the material of the second organic layer 30 can be increased by reducing the viscosity of the material of the second organic layer 30, so that the second organic layer 30 can fill the undercut opening 101 in the first organic layer 10.

[0072] In this embodiment, the viscosity of the material of the second organic layer 30 is reduced, which in turn reduces the density of the second organic layer 30 after film formation. The first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel. However, in this embodiment, 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 that of the first organic layer 10. Therefore, the density of the second organic layer 30 is less than that of the first organic layer 10. Furthermore, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0073] 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 by a vacuum drying process. In this embodiment, the vacuum time can be reduced, so that when the second organic layer 30 forms a film, it contains more solvent components and has less viscosity, which can improve the fluidity of the second organic layer 30 and make it easier for the second organic layer 30 to fill the undercut opening 101 in the first organic layer 10.

[0074] 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, such as propylene glycol methyl ether acetate. As the solvent content in the second organic layer 30 increases, the content of hydrogen and oxygen elements in the second organic layer 30 will also increase.

[0075] The first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel. However, in this embodiment, the process parameters for film formation of 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 that of the first organic layer 10. Therefore, the solvent content during film formation of the second organic layer 30 is greater than that during film formation of the first organic layer 10. Consequently, the hydrogen content in the second organic layer 30 is greater than that in the first organic layer 10, and / or, the oxygen content in the second organic layer 30 is greater than that in the first organic layer 10. Furthermore, the density of the second organic layer 30 is less than that of the first organic layer 10. Moreover, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0076] It is understood that, in this embodiment of the application, the coverage of the second organic layer 30 over the first organic layer 10 and the signal transmission unit 21 by reducing the viscosity of the material of the second organic layer 30 will be improved. However, the density and compactness of the second organic layer 30 will be reduced, which will in turn reduce the water and oxygen barrier performance of the planarization layer in the display panel. Therefore, in this embodiment of the application, the density of the first organic layer 10 can be increased accordingly to ensure that the water and oxygen barrier performance of the planarization layer in the display panel is not reduced, and the density of the first organic layer 10 can be greater than the density of the pixel definition layer 62.

[0077] 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 materials used to prepare the first organic layer 10 are the same as the raw materials used to prepare the second organic layer 30.

[0078] It should be noted that the first organic layer 10 has a protrusion 11 on the side near the signal transmission part 21. The orthographic projection of the protrusion 11 on the second organic layer 30 is located within the coverage area of ​​the orthographic projection of the signal transmission part 21 on the second organic layer 30. The protrusion 11 is formed by etching the first organic layer 10 with the displacement gas. The thickness of the etched part of the first organic layer 10 is reduced, and the part that is not etched due to the shielding of the signal transmission part 21 forms the protrusion 11.

[0079] Referring to Figures 2 and 4, in some embodiments, the protrusion 11 includes a first surface 111 near the signal transmission section 21 and a first side surface 112 connected to the first surface 111, and the signal transmission section 21 includes a second surface 211 away from the protrusion 11 and a second side surface 212 connected to the second surface 211.

[0080] In some embodiments, the first side 112 is recessed relative to the second side 212 toward the center of the protrusion 11 to form the undercut opening 101, and the second organic layer 30 covers the first side 112 and the second side 212.

[0081] In some embodiments, the angle A between the portion of the first side 112 near the first surface 111 and the first surface 111 is less than 90°, that is, the angle A can be an acute angle.

[0082] In some embodiments, the distance D inwardly recessed by the first side 112 relative to the second side 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 can be 0.1 micrometers, 0.2 micrometers, 0.3 micrometers, 0.4 micrometers or 0.5 micrometers.

[0083] The side of the protrusion 11 is recessed inward toward the center of the protrusion 11 relative to the side of the signal transmission part 21 to form the bottom cut opening 101. The second organic layer 30 covers the side of the protrusion 11 and the side of the signal transmission part 21. That is, the second organic layer 30 fills the bottom cut opening 101 and covers the inner wall of the bottom cut opening 101 to completely cover the first organic layer 10 and the signal transmission part 21, reducing the probability of the second organic layer 30 falling off.

[0084] Continuing from the above, this embodiment of the 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 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 undercut opening 101 in the first organic layer 10, thereby improving the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21, reducing the probability of the second organic layer 30 falling off, and improving the yield of the display panel.

[0085] In addition, this application embodiment also provides a method for manufacturing a display panel. Referring to Figures 2, 3, 5, and 6, the method for manufacturing the display panel includes the following steps:

[0086] S10, forming the first organic layer 10.

[0087] S20. A conductive layer 20 is formed on one side of the first organic layer 10, and a signal transmission section 21 is formed in the conductive layer 20.

[0088] S30. An undercut opening 101 is formed in the first organic layer 10 near the edge of the signal transmission section 21, and the undercut opening 101 at least partially overlaps with the signal transmission section 21 along the thickness direction of the display panel.

[0089] S40. A second organic layer 30 is formed on the side of the conductive layer 20 away from the first organic layer 10. The second organic layer 30 fills the undercut opening 101 and covers the signal transmission part 21. The density of the second organic layer 30 is different from the density of the first organic layer 10.

[0090] In one embodiment of this application, the step of forming the first organic layer includes:

[0091] A first organic material layer is applied and cured to obtain the first organic layer;

[0092] The step of forming a second organic layer on the side of the conductive layer away from the first organic layer includes:

[0093] A second organic material layer is coated on the side of the conductive layer away from the first organic layer and cured to obtain the second organic layer.

[0094] In one embodiment of this 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 device for coating the second organic material layer to the conductive layer is greater than or equal to 100 micrometers and less than or equal to 130 micrometers.

[0095] In one embodiment of this application, the viscosity of the second organic material layer is less than that of the first organic material layer.

[0096] Specifically, in step S10, a substrate 40 is first provided.

[0097] 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 transistors 51 include an active layer 511, a gate, a source 514, and a drain 515.

[0098] In some embodiments, the gate includes a first gate 512 disposed on the side of the active layer 511 away from the substrate 40 and a second gate 513 disposed on the side of the first gate 512 away from the active layer 511.

[0099] 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, an 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 the 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 54 disposed on the second gate insulating layer 54. The first gate 512 is located on the side away from the active layer 511, and a second gate 513 is disposed on the second gate insulating layer 54 and covers the second gate 513. A source 514 and a 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.

[0100] 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 may be coated on the side of the thin film transistor layer 50 away from the substrate 40 and the first organic material layer may be cured to obtain the first organic layer 10.

[0101] In step S20, a conductive material layer is formed on the side of the first organic layer 10 away from the thin film transistor layer 50. The conductive material layer may include a Ti / Al / Ti stacked structure.

[0102] Next, the conductive material layer is patterned to form the conductive layer 20, and the signal transmission section 21 is formed in the conductive layer 20.

[0103] For example, chlorine gas can be used to dry etch the conductive material layer. However, during etching, chlorine gas or chlorine elements may remain on the surface of the film, which can damage the film and affect subsequent processes.

[0104] In step S30, in order to prevent residual chlorine gas or chlorine elements from remaining on the surface of the film layer, which may damage the film layer and affect subsequent processes, this embodiment of the application may use a displacement gas to replace the surface of the first organic layer 10 and the conductive layer 20 to remove residual chlorine gas or chlorine elements. For example, the displacement gas may include oxygen.

[0105] The displacement gas etches the first organic layer 10. Due to the shielding effect of the signal transmission section 21 on the first organic layer 10, the displacement gas also etches horizontally at the edge of the signal transmission section 21 while etching the first organic layer 10 vertically. This results in the formation of the undercut opening 101 at the edge of the signal transmission section 21. Furthermore, the displacement gas etches the first organic layer 10 located at the edge of the signal transmission section 21 downwards towards the signal transmission section 21. Therefore, the undercut opening 101 and the signal transmission section 21 at least partially overlap along the thickness direction of the display panel.

[0106] In step S40, a second organic material layer 31 is coated on the 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 part 21.

[0107] In this embodiment, by changing the material properties or coating speed of the second organic layer 30, the second organic layer 30 can fill the undercut opening 101 in the first organic layer 10, thereby improving the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21, reducing the probability of the second organic layer 30 falling off, and improving the yield of the display panel.

[0108] In some embodiments of this application, the coating speed of the second organic layer 30 during the process 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.

[0109] 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 micrometers and less than or equal to 130 micrometers.

[0110] In this embodiment, the process parameters of the second organic layer 30 are adjusted to verify the coverage of the second organic layer 30 over the first organic layer 10.

[0111] Table 1 below shows the parameters and process conditions of the second organic layer 30 in Comparative Examples 1 to 3, and Examples 1 and 2 provided in this application.

[0112] As shown in Figure 6, and in Comparative Examples 1 to 3, as well as Examples 1 and 2, the second organic material layer 31 can be coated using the spraying structure shown in Figure 6 and then cured into a film to obtain the second organic layer 30.

[0113] Table 1

[0114] Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Second Organic Layer Film Thickness (micrometers) 2.7 2 2.7 2.7 2.7 Distance H (micrometers) 180 180 120 180 120 Coating Speed ​​(cm / min) 70 70 70 40 40 Undercut Opening Filling Result NG NGNGOKOK

[0115] In Comparative Example 1, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H from the nozzle 70 to the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 70 centimeters per minute.

[0116] In Comparative Example 2, the thickness of the second organic layer 30 is 2 micrometers, the distance H from the nozzle 70 to the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 70 cm / min.

[0117] In Comparative Example 3, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H from the nozzle 70 to the conductive layer 20 is 120 micrometers, and the coating speed of the nozzle 70 is 70 cm / min.

[0118] In Example 1, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H from the nozzle 70 to the conductive layer 20 is 180 micrometers, and the coating speed of the nozzle 70 is 40 cm / min.

[0119] In Example 2, the thickness of the second organic layer 30 is 2.7 micrometers, the distance H from the nozzle 70 to the conductive layer 20 is 120 micrometers, and the coating speed of the nozzle 70 is 40 cm / min.

[0120] As can be seen from Table 1, Examples 1 and 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 by reducing the coating speed of the second organic material layer 31, the embodiments of this application can effectively improve the coverage of the second organic layer 30 on the first organic layer 10 and reduce the probability of the second organic layer 30 falling off.

[0121] Furthermore, because the coating speed of the second organic layer 30 is slowed down, the second organic layer 30 has higher density and greater compactness after film formation. While the first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel, the coating speed of the first organic layer 10 is not changed in this embodiment, but 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. Furthermore, the elastic modulus of the second organic layer 30 is greater than the elastic modulus of the first organic layer 10.

[0122] In some embodiments of this application, the fluidity of the second organic material layer 31 can be increased by reducing the viscosity of the second organic material layer 31, so that the second organic layer 30 can fill the undercut opening 101 in the first organic layer 10.

[0123] In this embodiment, the viscosity of the second organic material layer 31 is reduced, which in turn reduces the density of the second organic layer 30 after film formation. The first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel. However, in this embodiment, 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 that of the first organic material layer. Therefore, the density of the second organic layer 30 is less than that of the first organic layer 10. Furthermore, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0124] 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 by a vacuum drying process. In this embodiment, the vacuum time can be reduced, so that when the second organic material layer 31 forms a film, it contains more solvent components and has less viscosity, which can improve the fluidity of the second organic material layer 31 and make it easier for the second organic material layer 31 to fill the undercut opening 101 in the first organic layer 10.

[0125] 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: carbon, hydrogen, and oxygen, such as propylene glycol methyl ether acetate. As the solvent content in the second organic layer 30 increases after film formation, the content of hydrogen and oxygen elements in the second organic layer 30 will also increase.

[0126] The first organic layer 10 and the second organic layer 30 both belong to the planarization layer in the display panel. However, in this embodiment, the process parameters for film formation of 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 that of the first organic layer 10. Therefore, the solvent content during film formation of the second organic layer 30 is greater than that during film formation of the first organic layer 10. Consequently, the hydrogen content in the second organic layer 30 is greater than that in the first organic layer 10, and / or, the oxygen content in the second organic layer 30 is greater than that in the first organic layer 10. Furthermore, the density of the second organic layer 30 is less than that of the first organic layer 10. Moreover, the elastic modulus of the second organic layer 30 is less than that of the first organic layer 10.

[0127] It is understood that, in this embodiment of the application, the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission unit 21 by reducing the viscosity of the second organic material layer 31 can be improved. However, the density and compactness of the second organic layer 30 will be reduced, which will in turn reduce the water and oxygen barrier performance of the planarization layer in the display panel. Therefore, in this embodiment of the application, the density of the first organic layer 10 can be increased accordingly to ensure that the water and oxygen barrier performance of the planarization layer in the display panel is not reduced, and the density of the first organic layer 10 can be greater than the density of the pixel definition layer 62.

[0128] 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 materials used to prepare the first organic layer 10 are the same as the raw materials used to prepare the second organic layer 30.

[0129] In summary, the embodiments of this application modify the properties or process parameters of the second organic layer 30 so that the density of the second organic layer 30 differs from that of the first organic layer 10. For example, by changing the material properties or coating speed of the second organic layer 30, the second organic layer 30 can fill the undercut opening 101 in the first organic layer 10, thereby improving the coverage of the second organic layer 30 on the first organic layer 10 and the signal transmission part 21, reducing the probability of the second organic layer 30 falling off, and improving the yield of the display panel.

[0130] In addition, this application embodiment also provides a display device, which includes the display panel described in the above embodiments.

[0131] It is understood that since the display device includes the display panel described in the above embodiments, the display device has the same beneficial effects as in the above embodiments, and will not be repeated here.

[0132] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0133] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0134] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0135] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

A display panel comprising: First organic layer; A conductive layer is disposed on one side of the first organic layer, and the conductive layer includes a signal transmission section; The second organic layer is disposed on the side of the conductive layer away from the first organic layer; The first organic layer has an undercut opening located at the edge of the signal transmission section. The undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer. The display panel of claim 1, wherein, The density of the second organic layer is greater than the density of the first organic layer. The display panel according to claim 1, wherein, The density of the second organic layer is less than that of the first organic layer. The display panel according to claim 3, wherein, The elastic modulus of the second organic layer is less than that of the first organic layer. The display panel according to claim 3, wherein, The hydrogen content in the second organic layer is greater than the hydrogen content in the first organic layer; And / or, the oxygen content in the second organic layer is greater than the oxygen content in the first organic layer. The display panel according to claim 3, wherein, The display panel further includes a pixel definition layer disposed on the side of the second organic layer away from the conductive layer, wherein the density of the first organic layer is greater than the density of the pixel definition layer. The display panel of claim 1, wherein, The display panel also includes: A substrate, wherein the first organic layer is disposed on the substrate; A thin-film transistor layer is disposed between the substrate and the first organic layer. The thin-film transistor layer includes a plurality of thin-film transistors, and each thin-film transistor includes an active layer, a gate, a source, and a drain. The signal transmission unit is connected to either the source or the drain. The display panel according to any one of claims 1 to 7, wherein The first organic layer has a protrusion on the side near the signal transmission part. The orthographic projection of the protrusion on the second organic layer is within the coverage area of ​​the orthographic projection of the signal transmission part on the second organic layer. The protrusion includes a first surface near the signal transmission part and a first side surface connected to the first surface. 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 is recessed inward relative to the second side in a direction close to the center of the protrusion to form the undercut opening, and the second organic layer covers the first side and the second side. The display panel according to claim 8, wherein, The angle between the portion of the first side closest to the first surface and the first surface is less than 90°. The display panel according to claim 8, wherein The first side is recessed inward relative to the second side in the direction closer to the center of the protrusion by a distance greater than 0 micrometers and less than or equal to 0.5 micrometers. A method for manufacturing a display panel, the method comprising the following steps: Formation of the first organic layer; A conductive layer is formed on one side of the first organic layer, and a signal transmission section is formed in the conductive layer; An undercut opening is formed in the first organic layer near the edge of the signal transmission section, and the undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel; A second organic layer is formed on the side of the conductive layer away from the first organic layer. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer. The method for manufacturing a display panel according to claim 11, wherein The step of forming the first organic layer includes: A first organic material layer is applied and cured to obtain the first organic layer; The step of forming a second organic layer on the side of the conductive layer away from the first organic layer includes: A second organic material layer is coated on the side of the conductive layer away from the first organic layer and cured to obtain the second organic layer. The method for manufacturing a display panel according to claim 12, wherein 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 micrometers and less than or equal to 130 micrometers. The method for manufacturing a display panel according to claim 12, wherein The viscosity of the second organic material layer is less than that of the first organic material layer. A display device includes a display panel, the display panel comprising: First organic layer; A conductive layer is disposed on one side of the first organic layer, and the conductive layer includes a signal transmission section; The second organic layer is disposed on the side of the conductive layer away from the first organic layer; The first organic layer has an undercut opening located at the edge of the signal transmission section. The undercut opening at least partially overlaps with the signal transmission section along the thickness direction of the display panel. The second organic layer fills the undercut opening and covers the signal transmission section. The density of the second organic layer is different from that of the first organic layer. The display device according to claim 15, wherein The density of the second organic layer is greater than the density of the first organic layer. The display device according to claim 15, wherein The density of the second organic layer is less than that of the first organic layer. The display device according to claim 17, wherein The elastic modulus of the second organic layer is less than that of the first organic layer. The display device according to claim 17, wherein The hydrogen content in the second organic layer is greater than the hydrogen content in the first organic layer; And / or, the oxygen content in the second organic layer is greater than the oxygen content in the first organic layer. The display device according to claim 17, wherein The display panel further includes a pixel definition layer disposed on the side of the second organic layer away from the conductive layer, wherein the density of the first organic layer is greater than the density of the pixel definition layer.

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