Display panel and manufacturing method thereof

Abstract

The application discloses a display panel and a manufacturing method thereof. The display panel comprises a substrate, a pixel definition layer and a light emitting unit. The display panel further comprises a partition structure. The partition structure is located in a non-opening area and is arranged on the pixel definition layer. The light emitting unit comprises a bottom electrode, a light emitting functional layer and a top electrode. The partition structure is used to partition the bottom electrodes of two adjacent light emitting units when the bottom electrode is deposited in an integral plane. The partition structure is formed by using a negative organic adhesive material. The radial width of the partition structure gradually decreases from the direction of the substrate. The application partitions the bottom electrodes of multiple light emitting units by using the partition structure. The etching process is not needed to remove the excess bottom electrode material, thereby reducing the influence of the etching process on the bottom electrode.

Description

Technical Field

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

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

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

[0004] The purpose of this application is to provide a display panel and a method for manufacturing the same. By setting a partition structure, when the bottom electrode of the light-emitting unit is formed, the bottom electrodes of multiple light-emitting units are isolated by the partition structure, so that the bottom electrodes of multiple light-emitting units are not connected to each other. This eliminates the need to remove excess bottom electrode material through an etching process, thereby reducing the impact of the etching process on the bottom electrode.

[0005] This application discloses a display panel, including a substrate, a pixel definition layer, and light-emitting units. The pixel definition layer is disposed on the substrate and has multiple opening areas. The light-emitting units are disposed on the substrate and located within the opening areas. The display panel also includes a partition structure located in a non-opening area and disposed on the pixel definition layer. The light-emitting unit includes a bottom electrode, a light-emitting functional layer, and a top electrode. The bottom electrode is disposed on the substrate, the light-emitting functional layer is disposed on the bottom electrode, and the top electrode is disposed on the light-emitting functional layer. The partition structure is used to isolate the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited using a full-surface deposition method. The partition structure is formed using a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction of the partition structure near the substrate.

[0006] Optionally, the partition structure is arranged around the opening area, and the cross-sectional shape of the partition structure is an inverted trapezoid; the side of the partition structure away from the substrate is the top surface, and the side of the partition structure close to the substrate is the bottom surface, and the angle between the top surface and the side surface is between 30 degrees and 70 degrees, or the angle between the side surface and the top surface of the pixel definition layer is between 30 degrees and 70 degrees.

[0007] Optionally, the thickness of the partition structure is greater than or equal to 0.01 μm and less than or equal to 0.06 μm; at the non-opening area, the radial width of the partition structure is less than or equal to the radial width of the pixel definition layer; the negative organic adhesive material includes polyimide material, epoxy resin material or polyester material.

[0008] Optionally, the thickness of the bottom electrode is greater than or equal to 0.01 μm and less than or equal to 0.03 μm, and the thickness of the partition structure is greater than or equal to 0.02 μm and less than or equal to 0.05 μm; in the partition structure, the angle between the top surface and the side surface is between 45 degrees and 60 degrees.

[0009] Optionally, the bottom electrode is a transparent electrode, formed using one or both of magnesium and silver materials; the top electrode is formed using a reflective metal material, and multiple light-emitting units share the top electrode; the light emitted by the light-emitting unit is emitted from one side of the substrate; the top electrode is the anode, and the bottom electrode is the cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer, and a hole transport layer, wherein the electron transport layer is disposed on the cathode, the light-emitting layer is disposed on the electron transport layer, the hole transport layer is disposed on the light-emitting layer, and the anode is disposed on the hole transport layer; the partition structure is used to isolate the cathodes of two adjacent light-emitting units when the cathode is deposited on an entire surface.

[0010] Optionally, the display panel further includes a cathode auxiliary electrode, which is formed of a transparent metal oxide material, disposed under the cathode and electrically connected to the cathode; the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer.

[0011] Optionally, the cathode further includes a redundant cathode electrode, which is disposed on the partition structure, and the cathode and the redundant cathode electrode are disconnected by the partition structure; the partition structure is also used to sequentially isolate the electron transport layer, the light emission layer and the hole transport layer between the opening region and the non-opening region during the full-surface deposition of the electron transport layer, the light emission layer and the hole transport layer.

[0012] This application discloses a method for manufacturing a display panel, including the following steps:

[0013] Provide a substrate;

[0014] A pixel definition layer is formed on the substrate, and the pixel definition layer is patterned to form multiple opening regions;

[0015] A partition structure is formed on the pixel definition layer;

[0016] The bottom electrode material is deposited over the entire surface, and the partition structure is used to isolate the bottom electrodes of two adjacent light-emitting units;

[0017] A light-emitting functional layer and a top electrode are sequentially formed in the opening area to form multiple light-emitting units;

[0018] The partition structure is formed using a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction of the partition structure near the substrate.

[0019] Optionally, the step of forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening regions includes:

[0020] A cathode auxiliary electrode material is deposited on the substrate, and after patterning, a cathode auxiliary electrode is formed in the opening region.

[0021] A pixel definition layer is deposited and patterned on the cathode auxiliary electrode. The cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and multiple opening regions are formed. The cathode auxiliary electrode is exposed from the opening regions.

[0022] Optionally, the step of sequentially forming a light-emitting functional layer and a top electrode in the opening region to form a plurality of light-emitting units includes:

[0023] The light-emitting functional layer material is deposited on the entire surface, and the light-emitting functional layers of two adjacent light-emitting units are separated by a hanging structure;

[0024] Anodes are deposited across the entire surface to form multiple light-emitting units;

[0025] Wherein, the top electrode is the anode, and the bottom electrode is the cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer, and a hole transport layer, wherein the electron transport layer is disposed on the cathode, the light-emitting layer is disposed on the electron transport layer, the hole transport layer is disposed on the light-emitting layer, and the anode is disposed on the hole transport layer;

[0026] The cathode is formed using one or both of magnesium and silver materials and is a light-transmitting electrode; the anode is formed using a reflective metal material and multiple light-emitting units share the anode; the light emitted by the light-emitting unit is emitted from one side of the substrate.

[0027] This application utilizes a negative organic adhesive material to form a partition structure. Firstly, the negative organic adhesive material allows for the formation of a partition structure that is wider at the top and narrower at the bottom during exposure and development. Secondly, the negative organic adhesive material possesses strong insulating properties; even without angle control during the full-surface deposition of the bottom electrode, the partition structure provides insulation when the bottom electrode is in contact with the partition structure, preventing electrical crosstalk between the bottom electrodes of adjacent light-emitting units. By setting the partition structure, this application isolates the bottom electrodes of multiple light-emitting units during the formation of the bottom electrode, ensuring that the bottom electrodes of multiple light-emitting units are not interconnected. During the formation of the bottom electrode, there is no need to remove excess bottom electrode material through an etching process; the next step of the light-emitting functional layer process can be performed directly after the full-surface deposition of the bottom electrode, reducing the impact of the etching process on the bottom electrode. Especially when the bottom electrode includes active metal materials, it avoids problems such as oxidation and residue of the active metal during the etching process, improves the film interface between the bottom electrode and the light-emitting functional layer, increases the luminous efficiency of the light-emitting unit, and enhances the display effect of the display panel. Attached Figure Description

[0028] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings:

[0029] Figure 1 This is a schematic diagram of the display panel according to the first embodiment of this application;

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

[0031] Figure 3 This is a schematic diagram of the partition structure of this application;

[0032] Figure 4 This is a schematic diagram of the light-emitting unit of this application;

[0033] Figure 5 This is a cross-sectional schematic diagram of the second type of display panel in this application;

[0034] Figure 6 This is a schematic diagram illustrating the steps of the method for manufacturing the display panel of this application;

[0035] Figure 7 This is a schematic diagram illustrating the manufacturing process of the display panel of this application.

[0036] Among them, 100 is the display panel; 101 is the opening area; 102 is the non-opening area; 110 is the substrate; 120 is the pixel definition layer; 130 is the light-emitting unit; 131 is the anode; 132 is the light-emitting functional layer; 1321 is the electron transport layer; 1322 is the light-emitting layer; 1323 is the hole transport layer; 1324 is the electron injection layer; 1325 is the hole blocking layer; 1326 is the electron blocking layer; 1327 is the hole injection layer; 133 is the cathode; 134 is the cathode auxiliary electrode; 135 is the cathode redundancy part; 140 is the partition structure; 150 is the driving circuit layer; 200 is the display device; and 210 is the driving circuit. Detailed Implementation

[0037] It should be understood that the terminology, specific structural and functional details used herein are merely for describing particular embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

[0038] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. Furthermore, terms indicating orientation or positional relationships, such as "upper," "lower," "left," "right," "vertical," and "horizontal," are described based on the orientation or relative positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description of this application, not indicating that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] The present application will now be described in detail with reference to the accompanying drawings and optional embodiments.

[0040] Figure 1 This is a schematic diagram of the first type of display panel of this application. Figure 2 yes Figure 1 See the schematic diagram of the cross-section along the cutting line AA. Figure 1-2As shown, this application discloses a display panel 100, which includes a substrate 110, a pixel definition layer 120, and light-emitting units 130. The pixel definition layer 120 is disposed on the substrate 110 and has a plurality of opening regions 101. The light-emitting units 130 are disposed on the substrate 110 and located within the opening regions 101. The display panel 100 also includes a partition structure 140, which is located in a non-opening region 102 and disposed on the pixel definition layer 120. The light-emitting units 130 include... The device includes a bottom electrode, a light-emitting functional layer 132, and a top electrode. The bottom electrode is disposed on the substrate 110, the light-emitting functional layer 132 is disposed on the bottom electrode, and the top electrode is disposed on the light-emitting functional layer 132. The partition structure 140 is used to isolate the bottom electrodes of two adjacent light-emitting units 130 when the bottom electrode is deposited on the entire surface. The partition structure 140 is formed of a negative organic adhesive material, and the radial width of the partition structure 140 gradually decreases from the direction of the partition structure 140 near the substrate 110.

[0041] This application utilizes a negative organic adhesive material to form the partition structure 140. Firstly, the negative organic adhesive material allows for the formation of a partition structure 140 that is wider at the top and narrower at the bottom during exposure and development. Secondly, the negative organic adhesive material possesses strong insulating properties; even without angle control during the full-surface deposition of the bottom electrode, the partition structure 140 still provides insulation when in contact with the bottom electrode, preventing electrical crosstalk between the bottom electrodes of adjacent light-emitting units 130. By setting the partition structure 140, this application isolates the bottom electrodes of multiple light-emitting units 130 during the formation of their bottom electrodes, ensuring that the bottom electrodes of multiple light-emitting units 130 are not interconnected. During the formation of the bottom electrode, there is no need to remove excess bottom electrode material through etching; the next step of the light-emitting functional layer 132 can be directly performed after the full-surface deposition of the bottom electrode, reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, problems such as oxidation and residue of the active metal during the etching process are avoided, the film interface between the bottom electrode and the light-emitting functional layer 132 is improved, the luminous efficiency of the light-emitting unit 130 is increased, and the display effect of the display panel 100 is improved.

[0042] Specifically, the negative organic adhesive material includes polyimide, epoxy resin, or polyester. The characteristic of this type of material is that the portion exposed to light polymerizes and cross-links, remaining as a functional structure, while the unexposed negative photosensitive organic material portion is removed by the developing solution in subsequent processes. Specifically, after coating a layer of negative organic adhesive material onto the substrate 110, due to the photosensitive properties of the negative organic adhesive material, the exposed portion polymerizes and cross-links after the film is formed. The stronger the light on the surface, the easier it is for the polymer to cross-link, while the light intensity gradually weakens in deeper areas, resulting in a lower degree of polymerization and cross-linking. Therefore, during the development process, the area with weakened photosensitive intensity below will be reacted, thus forming a structure that is wider at the top and narrower at the bottom. It is understood that the upper-wide, lower-narrow structure of the partition structure 140 in this application is integrally formed, and it is not necessary to use two or more layers of film to form the partition structure 140 by etching the width of different film layers.

[0043] Specifically, the partition structure 140 is arranged around the opening area 101, and the cross-sectional shape of the partition structure 140 is an inverted trapezoid.

[0044] In this embodiment, the cross-sectional shape of the partition structure 140 refers to the cross-section of the partition structure 140 on the line connecting two adjacent light-emitting units 130. The partition structure 140 adopts an inverted trapezoidal shape so that when the bottom electrode is deposited on the whole surface, it is separated by the wider upper part, so that the part of the bottom electrode material on the pixel definition layer 120 is not connected to the bottom electrode located in the opening area 101, thereby eliminating the need to etch away the bottom electrode material on the pixel definition layer 120 in the subsequent process, thus avoiding the problems caused by the etching process mentioned above.

[0045] Figure 3 This is a schematic diagram of the partition structure of this application, see below. Figure 3 As shown, to achieve the desired isolation of the bottom electrode, the angle of the inverted trapezoid needs to be controlled. Taking the side of the isolation structure 140 furthest from the substrate 110 as the top surface and the side of the isolation structure 140 closest to the substrate 110 as the bottom surface, the angle between the top surface and the side surface is between 30 and 70 degrees. When the angle between the top surface and the side surface approaches 90 degrees, the isolation effect is poor. During the deposition of the bottom electrode material, it is easy to deposit a film layer on the side surface of the isolation structure 140, resulting in a continuous distribution of the bottom electrode material from the pixel definition layer 120 to the side and top surfaces of the isolation structure 140. The smaller the angle between the top surface and the side surface, the more pronounced the concave effect of the side surface. During the deposition of the bottom electrode material, it is difficult to form a continuous film layer on the side surface of the isolation structure 140, thus failing to achieve the isolation effect. Relatively speaking, the smaller the angle between the top surface and the side surface, the higher the difficulty of the process. Relatively speaking, an angle between the top surface and the side surface of 30 degrees to 70 degrees has a better partitioning effect and is easier to achieve.

[0046] In other words, when the top surface of the pixel definition layer 120 below the partition structure 140 is parallel to the top surface of the partition structure 140, the angle θ between the side surface and the top surface of the pixel definition layer 120 is between 30 degrees and 70 degrees. Preferably, it is between 45 degrees and 60 degrees, which, considering the manufacturing process of the partition structure 140 and its partitioning effect on the light-emitting unit 130, has good implementation value.

[0047] In this embodiment, the bottom electrode and the light-emitting functional layer 132 are deposited using a vapor deposition process, specifically a maskless vapor deposition process. Maskless vapor deposition does not require a metal mask and directly uses an OH (overhang) structure to form the light-emitting functional layer 132. However, this embodiment also forms the bottom electrode using a maskless vapor deposition technique.

[0048] Specifically, the display panel 100 in this embodiment is a bottom-emitting display panel 100, wherein the bottom electrode is a light-transmitting electrode, the top electrode is formed of a reflective metal material, and the multiple light-emitting units 130 share the top electrode. In this embodiment, the top electrode is a high-reflectivity opaque electrode, and the bottom electrode is a light-transmitting electrode, so that all the light emitted by the light-emitting functional layer 132 is emitted from the bottom electrode, and the light emitted by the light-emitting unit 130 is emitted from one side of the substrate 110.

[0049] In this embodiment, the bottom electrode is patterned using the partition structure 140, and the light-emitting functional layer 132 is formed directly after the bottom electrode is patterned. This reduces other steps in the fabrication process of the bottom electrode and the light-emitting functional layer 132, such as etching steps, and greatly improves the film interface between the bottom electrode and the light-emitting functional layer 132. More importantly, the fabrication processes of the bottom electrode and the light-emitting functional layer 132 can be completed in the same vacuum environment, reducing film layer problems between the bottom electrode and the light-emitting functional layer 132.

[0050] It is worth mentioning that the advantage of the bottom-emitting display panel 100 is that the anode 131 does not need to be transparent, so the thickness of the anode 131 can be large, and it can be formed on the entire surface. All light-emitting units 130 share the same entire surface of the anode 131. Compared with the top electrode formed by indium tin oxide in the top-emitting display panel 100, the impedance drop is lower, and the components at different positions are more uniform, avoiding voltage differences at different positions. Moreover, since the emitted light from the light-emitting unit 130 does not need to pass through the subsequent encapsulation layer after the manufacturing process is completed, there is greater selectivity in the materials and processes of the encapsulation layer, which can achieve better encapsulation of the light-emitting unit 130.

[0051] Figure 4 This is a schematic diagram of the light-emitting unit of this application, see [link / reference]. Figure 4As shown, specifically, in order to further improve the luminous efficiency of the bottom-emitting display panel 100, this embodiment reverses the luminous functional layer 132. Specifically, the top electrode is the anode 131, and the bottom electrode is the cathode 133; the luminous functional layer 132 includes an electron transport layer 1321, a luminous layer 1322, and a hole transport layer 1323. The electron transport layer 1321 is disposed on the cathode 133, the luminous layer 1322 is disposed on the electron transport layer 1321, the hole transport layer 1323 is disposed on the luminous layer 1322, and the anode 131 is disposed on the hole transport layer 1323.

[0052] In this embodiment, the electron transport layer 1321 is connected to the cathode 133 via the electron injection layer 1324, and a hole blocking layer 1325 is also disposed between the electron transport layer 1321 and the light-emitting layer 1322. The hole transport layer 1323 is connected to the anode 131 via the hole injection layer 1327, and an electron blocking layer 1326 is also disposed between the hole transport layer 1323 and the light-emitting layer 1322. The inverted light-emitting functional layer 132 means that the electron transport layer 1321 is disposed on the side closer to the cathode 133, and the hole transport layer 1323 is disposed on the side closer to the anode 131. This is completely opposite to the light-emitting functional layer 132 in the light-emitting unit 130 of the upright organic light-emitting display panel 100. Relatively speaking, when the bottom-emitting display panel 100 uses a positively positioned light-emitting functional layer 132, the luminous efficiency is extremely low due to the low luminous efficiency. This, combined with the presence of an opening in the pixel driving layer, makes the bottom-emitting display panel 100 unsuitable for display applications. However, for the inverted bottom-emitting display panel 100, the luminous efficiency is affected by the work function of the anode 131 and the cathode 133. Generally, the work function of the anode 131 needs to be relatively high, and the work function of the cathode 133 relatively low. When the anode 131 is chosen as the reflective electrode and the cathode 133 as the transparent electrode, the material properties result in a lower work function for the anode 131 and a higher work function for the cathode 133, leading to lower luminous efficiency in the inverted bottom-emitting display panel 100.

[0053] In this embodiment, the cathode 133 is formed using one or both of magnesium and silver materials, and an active metal is used to form the cathode 133. The light transmittance is achieved by making the active metal thin. An indium tin oxide (ITO) or indium zinc oxide (IZO) material with a high work function is added to the anode 131, for example, by forming a layer of ITO or IZO material on the anode 131, to increase the work function of the anode 131.

[0054] When adding an active metal to the cathode 133, two aspects need to be considered. First, the transmittance of the active metal must be considered. The transmittance of a metal is related to its crystal structure, which refers to the arrangement of metal atoms according to a specific pattern. When the metal's crystal structure is sufficiently compact, leaving insufficient space for photons to pass through, the metal will exhibit opaque properties. However, if the metal thickness is reduced to a certain level, photons may be able to pass through the metal's crystal structure, making the metal transparent. The second aspect requires considering the work function. While setting the thickness based on transmittance, the work function must also be taken into account, as the thickness also affects the work function. Generally, taking the cathode 133 as an example, using an active metal material such as magnesium or silver, the thickness of the cathode 133 needs to be smaller than the thickness of the reflective metal layer in the anode 131 to achieve higher luminous efficiency. However, when the active metal material used in the cathode 133 is thin, such as between 100 angstroms and 300 angstroms, it is easy to be oxidized during the deposition and etching steps in the process. Specifically, in the etching process, there are also photoresist residues and etching problems, which will affect the work function of the cathode 133, resulting in a lower luminous efficiency of the inverted bottom light-emitting display panel 100.

[0055] Therefore, in this embodiment, when the thickness of the bottom electrode, i.e., the cathode 133, is greater than or equal to 100 angstroms and less than or equal to 300 angstroms, the isolation structure 140 allows multiple independent and unconnected cathodes 133 to be formed without etching, thus completely separating the cathodes 133 of adjacent light-emitting units 130. Even if a portion of the cathode redundancy 135 is formed on the isolation structure 140, this portion of the cathode redundancy 135 can also be disconnected from the cathode 133 to prevent current crosstalk. In this embodiment, the cathode 133 formed of an active metal material can reduce the work function of the cathode 133, thereby improving the imbalance between hole injection and electron injection in the inverted organic light-emitting display panel 100 and solving the problem of low luminous efficiency in the current inverted organic light-emitting display panel 100.

[0056] Specifically, the anode 131 is formed by depositing a reflective metal material over its entire surface, and multiple light-emitting units 130 share the anode 131. In order to match the work function of the cathode 133 and the light-emitting functional layer 132, the anode 131 in this embodiment can first be formed by sputtering a thin layer of indium tin oxide material with a thickness of about 0.01 mm to 0.1 mm, and then a high-reflectivity reflective metal material is vacuum-deposited, which can generally be silver. The thickness of the reflective metal material of the anode 131 is much thicker than that of the active metal material in the cathode 133.

[0057] Of course, the solution of this application can also be applied to the top-emitting display panel 100. For the top-emitting display panel 100, the bottom electrode of the display panel 100 is formed using a reflective electrode, and it can also be vapor-deposited through the partition structure 140 of this application, thus eliminating the need for an etching process. For example, the bottom electrode is formed using an opaque high-reflectivity electrode, while the top electrode is formed using a light-transmitting electrode. The bottom electrode is the anode 131, and the top electrode is the cathode 133. The patterned bottom electrode is directly formed through the partition structure 140, without the need to form the bottom electrode before the pixel definition layer 120 is formed.

[0058] Figure 5 This is a cross-sectional schematic diagram of the second type of display panel in this application, see [link / reference]. Figure 5 As shown, the inverted bottom light-emitting display panel 100 in this embodiment also includes a cathode auxiliary electrode 134. The cathode auxiliary electrode 134 is formed of a transparent metal oxide material. The cathode auxiliary electrode 134 is disposed under the cathode 133 and is electrically connected to the cathode 133. The cathode auxiliary electrodes 134 of two adjacent light-emitting units 130 are separated by the pixel definition layer 120.

[0059] To further improve the luminous efficiency of the light-emitting unit 130 of the inverted bottom-emitting display panel 100, this embodiment also provides a cathode auxiliary electrode 134 below the cathode 133. The light-transmitting metal oxide material of the cathode auxiliary electrode 134 includes one or both of indium tin oxide (ITO) and indium zinc oxide (IZO), and such materials have a light transmittance greater than 90%. The cathode auxiliary electrode 134 is connected to the pixel active switch in the driving circuit layer 150 through a via. It is understood that a driving circuit layer 150 is also provided on the substrate 110. The driving circuit layer 150 generally includes the pixel driving circuit of the light-emitting unit 130, such as the pixel active switch (thin-film transistor), data driving lines, scan control lines, etc. The cathode 133 of each light-emitting unit 130 is connected to the pixel active switch through the cathode auxiliary electrode 134, and the voltage of the cathode 133 is controlled by the pixel active switch.

[0060] Specifically, the cathode auxiliary electrodes 134 of two adjacent light-emitting units 130 are separated by the pixel definition layer 120. After the pixel driving layer process is completed, vias need to be set at the output end of the pixel active switch. After the vias are completed, the cathode auxiliary electrodes 134 are coated, and then the cathode auxiliary electrodes 134 are patterned. After retaining the cathode auxiliary electrodes 134 in multiple opening regions 101, the pixel definition layer 120 is formed. The pixel definition layer 120 covers part of the cathode auxiliary electrodes 134 and forms multiple openings, the positions of which are the opening regions 101. After forming the partition structure 140 on the pixel definition layer 120, the cathode 133 and the light-emitting functional layer 132 are isolated by the partition structure 140. In this embodiment, by setting the cathode auxiliary electrode 134, the problem of unstable connection performance caused by the need to connect the cathode 133, which uses active metal, to the thin-film pixel active switch is avoided.

[0061] It is worth mentioning that the cathode auxiliary electrodes 134 of two adjacent light-emitting units 130 are separated by a pixel definition layer 120. Considering that the cathode auxiliary electrodes 134 need to be directly connected to the cathodes 133 of each light-emitting unit 130, the cathode auxiliary electrodes 134 of adjacent light-emitting units 130 also need to be spaced apart to avoid electrical crosstalk problems. When the partition layer is formed of a metal material, since the partition layer is in direct contact with the cathode auxiliary electrodes 134, the partition layer of adjacent light-emitting units 130 also needs to be spaced apart.

[0062] Specifically, the cathode 133 further includes a redundant cathode 133 electrode, which is disposed on the partition structure 140. The cathode 133 and the redundant cathode 133 electrode are disconnected by the partition structure 140. The redundant cathode 133 electrode is formed during the formation of the cathode 133 on the pixel definition layer 120 using cathode 133 material deposited onto the pixel. The redundant cathode 133 electrode can be removed in subsequent processes, or it can remain in the process.

[0063] To avoid electrical connections between cathodes 133 and their redundant electrodes, the thickness of the isolation structure 140 needs to be limited, ensuring that the thickness h of the isolation structure 140 is at least greater than or equal to 0.01 μm. Of course, the thickness of the isolation structure 140 is also related to the thickness of the cathode 133, which is typically between 100 angstroms and 300 angstroms (0.01 μm to 0.03 μm). To meet the aforementioned requirements for transmittance and work function, in this case, the thickness h of the isolation structure 140 should be greater than or equal to 0.01 μm and less than or equal to 0.06 μm. This embodiment primarily considers that when the isolation structure 140 is only used to isolate the cathode 133, the thickness h of the isolation structure 140 does not need to exceed 0.06 μm. Specifically, a thickness of 0.02 μm and less than or equal to 0.05 μm for isolating the cathode 133 is effective.

[0064] In another embodiment, the partition structure 140 is also used to sequentially isolate one or more of the electron injection layer 1324, electron transport layer 1321, hollow blocking layer, light-emitting layer 1322, electron blocking layer 1326, hole transport layer 1323, and hole injection layer 1327 between the opening region 101 and the non-opening region 102 during the deposition of the entire light-emitting functional layer 132. However, considering that the required thickness of the partition structure 140 is relatively thick when using multi-layer partitioning, it leads to instability when forming the partition structure 140 using a negative organic adhesive material. Therefore, further considering that the electron transport layer 1321 in the light-emitting functional layer 132 isolates it, the crosstalk problem between the various light-emitting units 130 can be reduced. The thickness of the partition structure 140 can be controlled so that the partition structure 140 can isolate the cathode 133, electron injection layer 1324, and electron transport layer 1321. The thickness h of the partition structure 140 is greater than or equal to 0.02 μm and less than or equal to 0.15 μm. Specifically, when the thickness h of the partition structure 140 is greater than or equal to 0.04 μm and less than or equal to 0.1 μm, the partitioning effect on the cathode 133, electron injection layer 1324, and electron transport layer 1321 is better. It is worth mentioning that in this embodiment, the anode 131 needs to be formed using a full-surface deposition process. When the thickness of the partition structure 140 is greater, the anode 131 will also be partitioned. Therefore, the thickness of the partition structure 140 should not be too large, i.e., less than or equal to 0.15 μm. Of course, the thicker the partition structure 140, the stronger its partitioning ability, enabling thicker film layers to be partitioned. If the anode 131 is also partitioned, the thickness of the anode 131 can be increased to partially partition it. However, since the thickness of the anode 131 is sufficient, the anode 131 will not be completely partitioned.

[0065] Figure 6 This is a schematic diagram illustrating the steps of the method for manufacturing the display panel of this application. Figure 7This is a schematic diagram illustrating the manufacturing process of the display panel of this application. See [link / reference]. Figures 6 to 7 As shown, this application also discloses a method for manufacturing a display panel, including the following steps:

[0066] S110: Provides a substrate;

[0067] S120: A pixel definition layer is formed on the substrate, and the pixel definition layer is patterned to form a plurality of opening regions;

[0068] S130: Form a partition structure on the pixel definition layer;

[0069] S140: The bottom electrode material is deposited on the entire surface, and the partition structure is used to partition the bottom electrodes of two adjacent light-emitting units;

[0070] S150: A light-emitting functional layer and a top electrode are sequentially formed in the opening area to form multiple light-emitting units;

[0071] The partition structure 140 is formed using a negative organic adhesive material, and the radial width of the partition structure 140 gradually decreases from the direction of the partition structure 140 approaching the substrate 110.

[0072] This application utilizes a negative organic adhesive material to form the partition structure 140. Firstly, the negative organic adhesive material allows for the formation of a partition structure 140 that is wider at the top and narrower at the bottom during exposure and development. Secondly, the negative organic adhesive material possesses strong insulating properties; even without angle control during the full-surface deposition of the bottom electrode, the partition structure 140 still provides insulation when in contact with the bottom electrode, preventing electrical crosstalk between the bottom electrodes of adjacent light-emitting units 130. By setting the partition structure 140, this application isolates the bottom electrodes of multiple light-emitting units 130 during the formation of their bottom electrodes, ensuring that the bottom electrodes of multiple light-emitting units 130 are not interconnected. During the formation of the bottom electrode, there is no need to remove excess bottom electrode material through etching; the next step of the light-emitting functional layer 132 can be directly performed after the full-surface deposition of the bottom electrode, reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, problems such as oxidation and residue of the active metal during the etching process are avoided, the film interface between the bottom electrode and the light-emitting functional layer 132 is improved, the luminous efficiency of the light-emitting unit 130 is increased, and the display effect of the display panel 100 is improved.

[0073] In this embodiment, an inverted bottom-emitting display panel 100 is used as an example for description. However, the manufacturing method of the display panel 100 provided in this application is not limited to manufacturing an inverted bottom-emitting display panel 100. The upright bottom-emitting display panel 100 in the above embodiment is also applicable to the manufacturing process method in this embodiment. Specifically, the top electrode is an anode 131, the bottom electrode is a cathode 133, and the light-emitting functional layer 132 includes an electron transport layer 1321, a light-emitting layer 1322, and a hole transport layer 1323. The electron transport layer 1321 is disposed on the cathode 133, the light-emitting layer 1322 is disposed on the electron transport layer 1321, the hole transport layer 1323 is disposed on the light-emitting layer 1322, and the anode 131 is disposed on the hole transport layer 1323. The cathode 133 is formed using one or both of magnesium and silver materials and is a light-transmitting electrode. The anode 131 is formed using a reflective metal material, and multiple light-emitting units 130 share the anode 131. The light emitted by the light-emitting unit 130 is emitted from one side of the substrate 110.

[0074] Before step S120, the process includes forming a driving circuit layer 150 on the substrate 110. This driving circuit layer 150 includes multiple thin-film transistors and driving lines, forming a driving circuit for driving multiple light-emitting units 130 to emit light. During the formation of the driving circuit layer 150, vias are provided for the thin-film transistors corresponding to the light-emitting units 130. These vias are used to connect a cathode auxiliary electrode 134 between the thin-film transistor and the cathode 133 of the light-emitting unit 130.

[0075] The steps in S120 also include the following steps:

[0076] S121: A cathode auxiliary electrode material is deposited on the substrate and patterned to form a cathode auxiliary electrode in the opening region;

[0077] S122: A pixel definition layer is deposited and patterned on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and multiple opening regions are formed, the cathode auxiliary electrode is exposed from the opening regions.

[0078] In this embodiment, after the process of the driving circuit layer 150 is completed, a cathode auxiliary electrode 134 is formed in the opening region 101, and the cathode auxiliary electrode 134 is connected to the output terminal of the thin film transistor at the via position of the driving circuit layer 150 to realize voltage control of the cathode 133.

[0079] In one embodiment, step S150 includes:

[0080] S151: Deposit the light-emitting functional layer material over the entire surface, and isolate the light-emitting functional layers of two adjacent light-emitting units through a partition structure;

[0081] S152: Deposit the anode across the entire surface to form multiple light-emitting units.

[0082] In this design, a light-emitting functional layer 132 of the light-emitting unit 130 is formed by a partition structure 140. The light-emitting functional layer 132 may include an electron injection layer 1324, an electron transport layer 1321, a hole blocking layer 1325, a light-emitting layer 1322, an electron blocking layer 1326, a hole transport layer 1323, and a hole injection layer 1327, which are sequentially arranged from the cathode 133 toward the anode 131. In this embodiment, the thickness of the partition structure 140 can be adjusted to prevent the anode 131 from being blocked, thereby forming a full-surface anode 131.

[0083] This application utilizes a negative organic adhesive material to form the partition structure 140. Firstly, the negative organic adhesive material allows for the formation of a partition structure 140 that is wider at the top and narrower at the bottom during exposure and development. Secondly, the negative organic adhesive material possesses strong insulating properties; even without angle control during the full-surface deposition of the bottom electrode, the partition structure 140 still provides insulation when in contact with the bottom electrode, preventing electrical crosstalk between the bottom electrodes of adjacent light-emitting units 130. By setting the partition structure 140, this application isolates the bottom electrodes of multiple light-emitting units 130 during the formation of their bottom electrodes, ensuring that the bottom electrodes of multiple light-emitting units 130 are not interconnected. During the formation of the bottom electrode, there is no need to remove excess bottom electrode material through etching; the next step of the light-emitting functional layer 132 can be directly performed after the full-surface deposition of the bottom electrode, reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, problems such as oxidation and residue of the active metal during the etching process are avoided, the film interface between the bottom electrode and the light-emitting functional layer 132 is improved, the luminous efficiency of the light-emitting unit 130 is increased, and the display effect of the display panel 100 is improved.

[0084] It should be noted that the inventive concept of this application can form many embodiments, but due to the limited space of the application documents, they cannot all be listed. Therefore, without conflict, the embodiments described above or the technical features can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effect will be enhanced.

[0085] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A method for manufacturing a display panel, characterized in that, The method comprises the steps of: providing a substrate; forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening regions, including: depositing a cathode auxiliary electrode material on the substrate, and patterning to form a cathode auxiliary electrode in the opening regions; depositing and patterning a pixel definition layer on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light emitting units being separated by the pixel definition layer, and a plurality of opening regions being formed, the cathode auxiliary electrode being exposed from the opening regions; forming a partition structure on the pixel definition layer; depositing a bottom electrode material on the entire surface, the partition structure being used to separate the bottom electrodes of two adjacent light emitting units; forming a light emitting functional layer and a top electrode in the opening regions in sequence to form a plurality of light emitting units, including: depositing a light emitting functional layer material on the entire surface, and separating the light emitting functional layers of two adjacent light emitting units through the overhang structure; and depositing an anode on the entire surface to form a plurality of light emitting units; wherein the top electrode is an anode, the bottom electrode is a cathode, the cathode is a light-transmitting electrode, the anode is formed of a reflective metal material, and the plurality of light emitting units share the anode, and light emitted by the light emitting units is emitted from one side of the substrate; wherein the partition structure is formed of a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the side of the partition structure close to the substrate; the cathode auxiliary electrode is arranged below the cathode and is electrically connected to the cathode.

2. The method of manufacturing a display panel according to claim 1, wherein the partition structure is arranged around the opening regions, and the cross-sectional shape of the partition structure is an inverted trapezoid; the side of the partition structure away from the substrate is a top surface, the side of the partition structure close to the substrate is a bottom surface, the included angle between the top surface of the partition structure and the side surface of the partition structure is between 30 degrees and 70 degrees, or the included angle between the side surface of the partition structure and the top surface of the pixel definition layer is between 30 degrees and 70 degrees.

3. The manufacturing method of a display panel according to claim 2, wherein the thickness of the partition structure is greater than or equal to 0.01 um and less than or equal to 0.06 um; at the position of the non-opening region, the radial width of the partition structure is less than or equal to the radial width of the pixel definition layer; the negative organic adhesive material includes a polyimide material, an epoxy resin material, or a polyacid ester material.

4. The manufacturing method of a display panel according to claim 3, wherein the thickness of the bottom electrode is greater than or equal to 0.01 um and less than or equal to 0.03 um, and the thickness of the partition structure is greater than or equal to 0.02 um and less than or equal to 0.05 um; in the partition structure, the included angle between the top surface and the side surface is between 45 degrees and 60 degrees.

5. The method of manufacturing a display panel according to claim 1, wherein the cathode is formed of one or both of magnesium material and silver material; the light emitting functional layer includes an electron transport layer, a light emitting layer, and a hole transport layer, the electron transport layer is arranged on the cathode, the light emitting layer is arranged on the electron transport layer, the hole transport layer is arranged on the light emitting layer, and the anode is arranged on the hole transport layer.

6. The manufacturing method of a display panel according to claim 5, wherein the cathode auxiliary electrode is formed of a transparent metal oxide material.

7. The manufacturing method of a display panel according to claim 5, wherein the cathode further includes a cathode redundant electrode, the cathode redundant electrode is arranged on the partition structure, and the cathode and the cathode redundant electrode are disconnected through the partition structure. The partition structure is also used to sequentially partition the electron transport layer, the light emitting layer and the hole transport layer between the open area and the non-open area when the electron transport layer, the light emitting layer and the hole transport layer are deposited in the whole surface.

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