Display panel and manufacturing method thereof

Abstract

The invention 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, and the partition structure is located in a non-opening area and arranged on the pixel definition layer; each light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, and the partition structure is used for partitioning the bottom electrodes of two adjacent light-emitting units when the bottom electrodes are subjected to whole-surface deposition; wherein the partition structure is made of a negative organic adhesive material, and the radial width of the partition structure is gradually reduced in the direction, close to the substrate, of the partition structure. According to the invention, the bottom electrodes of the plurality of light-emitting units are separated by using the separation structures, and redundant bottom electrode materials do not need to be removed through an etching process, so that the influence of the etching process on the bottom electrodes is reduced.

Description

Technical Field

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

[0002] OLED (Organic Light Emitting Diode) display devices are widely used in various fields due to their light weight, wide viewing angle, fast response, low temperature resistance, high luminous efficiency, and the ability to produce curved flexible displays. As mass production technology becomes increasingly mature, OLED display panels are gradually becoming mainstream real panels.

[0003] Existing organic light-emitting display panels mainly include two categories, one is an upright organic light-emitting display panel, wherein the light-emitting unit in the upright organic light-emitting display panel includes an anode, a light-emitting functional layer and a cathode stacked in sequence from a base substrate; the other is an inverted organic light-emitting display panel, which includes a cathode, a light-emitting functional layer and an anode stacked in sequence from a base substrate. For an upright organic light-emitting display panel, the active metal in the cathode is easily corroded by water and oxygen, resulting in a reduction in the life of the display panel. For an inverted organic light-emitting display panel, the active metal in the cathode is also easily oxidized during the manufacturing process or has problems such as process residues, resulting in low luminous efficiency of the inverted organic light-emitting display panel. In this regard, the art is in urgent need of a solution to the above problems. Summary of the invention

[0004] The purpose of the present application is to provide a display panel and a method for manufacturing the same. By setting a partition structure, when a light-emitting unit forms a bottom electrode, the partition structure is used to isolate the bottom electrodes of multiple light-emitting units, so that the bottom electrodes of the multiple light-emitting units are not connected to each other, and there is no need to remove excess bottom electrode material through an etching process, thereby reducing the impact of the etching process on the bottom electrode.

[0005] The present application discloses a display panel, comprising a base substrate, a pixel definition layer and a light-emitting unit, wherein the pixel definition layer is arranged on the base substrate and is provided with a plurality of opening areas, and the light-emitting unit is arranged on the base substrate and is located in the opening areas; the display panel also comprises a partition structure, wherein 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, wherein the bottom electrode is arranged on the base substrate, the light-emitting functional layer is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer; the partition structure is used to partition the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited on the entire surface; wherein the partition structure is formed by a negative organic glue material, and the radial width of the partition structure gradually decreases from the direction in which the partition structure approaches the base 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 base substrate is the top surface, and the side of the partition structure close to the base 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 0.01um and less than or equal to 0.06um; 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 glue material includes polyimide material, epoxy resin material or polyester material.

[0008] Optionally, the thickness of the bottom electrode is greater than or equal to 0.01um and less than or equal to 0.03um, and the thickness of the partition structure is greater than or equal to 0.02um and less than or equal to 0.05um; 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 light-transmitting electrode, formed of one or both of magnesium material and silver material; the top electrode is formed of a reflective metal material, and a plurality of the 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 an anode, and the bottom electrode is a cathode; 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; the partition structure is used to separate the cathodes of two adjacent light-emitting units when the cathode is deposited on the entire surface.

[0010] Optionally, the display panel also includes a cathode auxiliary electrode, which is formed of a transparent metal oxide material, is arranged under the cathode, and is 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 also includes a cathode redundant electrode, which is arranged on the partition structure, and the cathode and the cathode redundant electrode are disconnected by the partition structure; the partition structure is also used to sequentially isolate the electron transport layer, the light-emitting layer and the hole transport layer between the opening area and the non-opening area when the electron transport layer, the light-emitting layer and the hole transport layer are deposited on the entire surface.

[0012] The present application discloses a method for manufacturing a display panel, comprising the steps of:

[0013] Providing a substrate;

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

[0015] forming a partition structure on the pixel definition layer;

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

[0017] Sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units;

[0018] The partition structure is formed of a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction in which the partition structure approaches the base 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 areas includes:

[0020] Depositing cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning;

[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 a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

[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] Depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by an overhanging structure;

[0024] Depositing anodes on the entire surface to form a plurality of the light-emitting units;

[0025] Wherein, the top electrode is an anode, and the bottom electrode is a cathode; 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;

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

[0027] The present application forms a partition structure by using a negative organic glue material. First, the negative organic glue material can form a partition structure with a wide upper part and a narrow lower part during the exposure and development process. Secondly, the negative organic glue material has a strong insulating property. Even if the angle is not controlled during the deposition of the entire surface of the bottom electrode, the bottom electrode contacts the partition structure, and the partition structure can also play an insulating role to prevent the electrical crosstalk between the bottom electrodes of adjacent light-emitting units. The present application sets a partition structure. When the bottom electrode is formed in the light-emitting unit, the partition structure is used to isolate the bottom electrodes of multiple light-emitting units, so that the bottom electrodes of multiple light-emitting units are not connected to each other. In the process of forming the bottom electrode, it is not necessary to remove the excess bottom electrode material through an etching process. The next step of the light-emitting functional layer process can be directly carried out after the bottom electrode is deposited on the entire surface, reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, the active metal is avoided from being oxidized and remaining in the etching process, the film interface between the bottom electrode and the light-emitting functional layer is improved, the light-emitting efficiency of the light-emitting unit is improved, and the display effect of the display panel is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

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

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

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

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

[0033] Figure 5 is a cross-sectional schematic diagram of a second display panel of the present application;

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

[0035] Figure 7 It is a schematic diagram of the manufacturing process of the display panel of the present application.

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

[0037] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative, but the present application can be implemented in many alternative forms and should not be construed as being limited to only the embodiments described herein.

[0038] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; "multiple" means two or more. In addition, the terms "upper", "lower", "left", "right", "vertical", "horizontal", etc. indicating orientation or positional relationships are described based on the orientation or relative positional relationships shown in the accompanying drawings, and are only for the convenience of describing the simplified description of the present application, rather than indicating that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0039] The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0040] Figure 1 is a schematic diagram of the first display panel of the present application, Figure 2 yes Figure 1 Schematic diagram of the cross section along the cutting line AA, see Figure 1-2As shown, the present application discloses a display panel, the display panel 100 includes a base substrate 110, a pixel definition layer 120 and a light emitting unit 130, the pixel definition layer 120 is arranged on the base substrate 110 and is provided with a plurality of opening areas 101, the light emitting unit 130 is arranged on the base substrate 110 and is located in the opening area 101, the display panel 100 also includes a partition structure 140, the partition structure 140 is located in the non-opening area 102 and is arranged on the pixel definition layer 120; the light emitting unit 130 includes The light-emitting functional layer 132 comprises a bottom electrode, a light-emitting functional layer 132 and a top electrode, wherein the bottom electrode is arranged on the base substrate 110, the light-emitting functional layer 132 is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer 132; the partition structure 140 is used to separate the bottom electrodes of two adjacent light-emitting units 130 when the bottom electrode is deposited on the entire surface; wherein the partition structure 140 is formed by a negative organic glue material, and the radial width of the partition structure 140 gradually decreases from the direction in which the partition structure 140 approaches the base substrate 110.

[0041] The present application forms the partition structure 140 by using a negative organic glue material. First, the negative organic glue material can form a partition structure 140 with a wide upper part and a narrow lower part during the exposure and development process. Secondly, the negative organic glue material has strong insulation properties. Even if the angle is not controlled during the deposition of the entire surface of the bottom electrode, the bottom electrode is in contact with the partition structure 140. The partition structure 140 can also play an insulating role to prevent the electrical crosstalk problem between the bottom electrodes of adjacent light-emitting units 130. The present application sets a partition structure 140. When the bottom electrode is formed in the light-emitting unit 130, the partition structure 140 is used to isolate the bottom electrodes of multiple light-emitting units 130, so that the bottom electrodes of multiple light-emitting units 130 are not connected to each other. In the process of forming 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 132 process can be directly carried out after the bottom electrode is deposited on the entire surface, thereby reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes active metal materials, the problems of 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 improved, and the display effect of the display panel 100 is improved.

[0042] Specifically, negative organic glue materials include polyimide materials, epoxy resin materials or polyester materials, etc. The characteristics of this type of material are that the illuminated part will polymerize and cross-link to remain as a functional structure, and the part of the negative photosensitive organic material that is not illuminated will be removed by the developer in the subsequent process. Specifically, after a layer of negative organic glue material is coated on the substrate 110, due to the photosensitivity of the negative organic glue material, after the negative organic glue material is coated into a film, the illuminated part will polymerize and cross-link, so that the stronger the light on the surface, the easier it will be to polymerize and cross-link, and the light intensity will gradually weaken in deeper places, and the degree of polymerization and cross-linking is not as good as the surface. Therefore, during the development process, the part below where the photosensitivity intensity is weakened will be reacted, thereby forming a structure that is wide at the top and narrow at the bottom. It can be understood that the structure of the partition structure 140 of the present application, which is wide at the top and narrow at the bottom, is formed in one piece, and does not require the use of two or more film layers. The partition structure 140 is formed by etching the width of different film layers.

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

[0044] In the present embodiment, the cross-sectional shape of the partition structure 140 refers to the cross-sectional shape of the partition structure 140 on the line between 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 entire surface, it is separated by a wider upper part, so that the portion of the bottom electrode material located on the pixel definition layer 120 is not connected to the bottom electrode located in the opening area 101, thereby eliminating the need for subsequent etching of the bottom electrode material on the pixel definition layer 120, thereby avoiding the problems caused by the etching process mentioned above.

[0045] Figure 3 is a schematic diagram of the partition structure of this application, see Figure 3 As shown, in order to separate the bottom electrode, the angle of the inverted trapezoid needs to be controlled. Taking the side of the partition structure 140 away from the base substrate 110 as the top surface and the side of the partition structure 140 close to the base substrate 110 as the bottom surface, the angle between the top surface and the side surface is between 30 degrees and 70 degrees. When the angle between the top surface and the side surface approaches 90 degrees, the separation effect is poor. During the deposition of the bottom electrode material, it is easy to deposit a film layer on the side of the partition structure 140, so that the bottom electrode material is continuously distributed from the pixel definition layer 120 to the side and top surface of the partition structure 140. When the angle between the top surface and the side surface is smaller, the concave effect of the side surface is more obvious. When the bottom electrode material is deposited, it is difficult to form a continuous film layer on the side of the partition structure 140, thereby achieving the separation effect. Relatively speaking, the smaller the angle between the top surface and the side surface, the higher the difficulty of the process required. Relatively speaking, the angle between the top surface and the side surface between 30 degrees and 70 degrees has a better partition 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. Among them, 45 degrees to 60 degrees is preferred, which has a better implementation value in terms of the process of the partition structure 140 and the partition effect on the light-emitting unit 130.

[0047] The bottom electrode and the light-emitting functional layer 132 in this embodiment may be deposited by an evaporation process, specifically a maskless evaporation process, which 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 by a maskless evaporation technique.

[0048] Specifically, the display panel 100 of 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 top electrode is shared by a plurality of the light-emitting units 130. The top electrode in this embodiment is a high-reflectivity light-impermeable 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 base substrate 110.

[0049] In this embodiment, the bottom electrode is patterned through the partition structure 140, and the light-emitting functional layer 132 is directly formed after the bottom electrode is patterned, which reduces other steps in the process of the bottom electrode and the light-emitting functional layer 132, such as the etching step, and greatly improves the film interface between the bottom electrode and the light-emitting functional layer 132. More importantly, the process of the bottom electrode and the process of the light-emitting functional layer 132 can be completed in the same vacuum environment, reducing the film problem 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 light-transmissive, so the thickness of the anode 131 can be very large and can be formed on the entire surface. All light-emitting units 130 share the entire surface of the anode 131, which has a lower resistance drop than the top electrode formed of indium tin oxide in the top-emitting display panel 100, and the components at different positions are more uniform, avoiding different voltages at different positions. Moreover, after the light-emitting unit 130 completes the process, the emitted light of the light-emitting unit 130 does not need to pass through the subsequent encapsulation layer, so the selectivity of the material and process of the encapsulation layer is greater, and better encapsulation of the light-emitting unit 130 can be achieved.

[0051] Figure 4 is a schematic diagram of the light-emitting unit of the present application, see Figure 4As shown, specifically, in order to further improve the luminous efficiency of the bottom-emitting display panel 100, the present embodiment inverts 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 luminescent layer 1322, and a hole transport layer 1323, wherein the electron transport layer 1321 is disposed on the cathode 133, the luminescent layer 1322 is disposed on the electron transport layer 1321, the hole transport layer 1323 is disposed on the luminescent layer 1322, and the anode 131 is disposed on the hole transport layer 1323.

[0052] The electron transport layer 1321 in this embodiment is connected to the cathode 133 through the electron injection layer 1324, and a hole blocking layer 1325 is further provided between the electron transport layer 1321 and the light-emitting layer 1322. The hole transport layer 1323 is connected to the anode 131 through the hole injection layer 1327, and an electron blocking layer 1326 is further provided 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 provided on the side close to the cathode 133, and the hole transport layer 1323 is provided on the side close to the anode 131. This is completely opposite to the light-emitting functional layer 132 in the light-emitting unit 130 of the upright organic light-emitting display panel 100. Relatively speaking, when the bottom-emitting display panel 100 uses the light-emitting functional layer 132 as a positive solution, due to the low luminous efficiency and the influence of the pixel driving layer opening of the bottom-emitting display panel 100, the luminous efficiency of the bottom-emitting display panel 100 with the positive light-emitting functional layer 132 is extremely low, and it is not suitable for display. However, for the inverted bottom-emitting display panel 100, the luminous efficiency is affected by the work functions of the anode 131 and the cathode 133. Generally speaking, the work function of the anode 131 is relatively high, and the work function of the cathode 133 is relatively low. When the anode 131 is selected as a reflective electrode and the cathode 133 is selected as a light-transmitting electrode, due to the characteristics of the materials, the work function of the anode 131 will be low, and the work function of the cathode 133 will be high, resulting in a low luminous efficiency of the inverted bottom-emitting display panel 100.

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

[0054] In the case of adding active metal to the cathode 133, two aspects need to be considered. The first aspect is the light transmittance of the active metal. The transmittance of the metal is related to its lattice structure, which refers to the way in which metal atoms are arranged according to a specific rule. When the lattice structure of the metal is tight enough and there is not enough space for photons to pass through, the metal will show an opaque characteristic. If the thickness of the metal is reduced to a certain extent, photons may pass through the lattice structure of the metal, making the metal translucent. Another solution needs to consider the work function. While setting the thickness considering the light transmittance, the work function also needs to be taken into account, and its thickness also affects the work function. Generally speaking, taking the cathode 133 as an example of being formed of an active metal material, and the active metal material is 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 a higher luminous efficiency. However, when the active metal material used for the cathode 133 is relatively thin, for example, 100 angstroms to 300 angstroms, it is easily 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, thereby causing the inverted bottom-emitting display panel 100 to have a low luminous efficiency.

[0055] Therefore, when the thickness of the bottom electrode, i.e., the cathode 133, of the present embodiment is greater than or equal to 100 angstroms and less than or equal to 300 angstroms, the partitioning effect of the partitioning structure 140 allows the cathode 133 to be formed into a plurality of independent and non-interconnected cathodes 133 without etching, so that the cathodes 133 of adjacent light-emitting units 130 are completely separated. Even if a partial cathode redundant portion 135 is formed on the partitioning structure 140, the partial cathode redundant portion 135 can be disconnected from the cathode 133 to prevent the problem of current crosstalk. The cathode 133 formed of an active metal material in the present embodiment can reduce the work function of the cathode 133 to improve the phenomenon that hole injection and electron injection in the inverted organic light-emitting display panel 100 cannot be balanced, thereby solving the problem of low light-emitting efficiency of the current inverted organic light-emitting display panel 100.

[0056] Specifically, the anode 131 is formed by depositing a reflective metal material on the entire surface, and the 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 of this embodiment can first adopt a sputtering process to form a thinner layer of indium tin oxide material with a thickness of about 0.01mm to 0.1mm, and then vacuum evaporate a reflective metal material with high reflectivity, which can generally be a silver material, and the thickness of the reflective metal material of the anode 131 is much thicker than the active metal material in the cathode 133.

[0057] Of course, the solution of the present 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 by a reflective electrode, and can also be evaporated by the partition structure 140 of the present application, so that no etching process is required. For example, the bottom electrode is formed by an opaque high-reflective electrode, and the top electrode is formed by a transparent electrode. The bottom electrode is the anode 131, and the top electrode is the cathode 133. The patterned bottom electrode is directly formed by the partition structure 140, and there is no need to form the bottom electrode before the pixel definition layer 120 is formed.

[0058] Figure 5 is a cross-sectional schematic diagram of the second display panel of the present application, see Figure 5 As shown, the inverted bottom-emitting display panel 100 of this embodiment also includes a cathode auxiliary electrode 134, which is formed of a transparent metal oxide material. The cathode auxiliary electrode 134 is arranged 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] In order to further improve the luminous efficiency of the light-emitting unit 130 of the inverted bottom-emitting display panel 100, the present embodiment further 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 material (ITO) or indium zinc oxide material (IZO), and the light transmittance of such material is greater than 90% of the metal material. The cathode auxiliary electrode 134 is connected to the pixel active switch in the driving circuit layer 150 through a via hole. It can be understood that a driving circuit layer 150 is also provided on the base substrate 110. The driving circuit layer 150 generally includes a pixel driving circuit of the light-emitting unit 130, such as a pixel active switch (thin film transistor), a data driving line, a scanning control line, 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 process of the pixel driving layer is completed, a via hole needs to be set at the output end of the pixel active switch. After the via hole is completed, the cathode auxiliary electrode 134 is coated, and then the cathode auxiliary electrode 134 is patterned. After retaining the cathode auxiliary electrodes 134 in multiple opening areas 101, the pixel definition layer 120 is formed. The pixel definition layer 120 covers part of the cathode auxiliary electrode 134 and forms multiple openings. The position of the opening is the opening area 101. After the partition structure 140 is formed on the pixel definition layer 120, the partition structure 140 is used to partition the cathode 133 and the light-emitting functional layer 132. In this embodiment, by setting the cathode auxiliary electrode 134, the problem of unstable connection performance caused by the cathode 133 using active metal needing to be connected 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 the pixel definition layer 120. Considering that the cathode auxiliary electrode 134 needs to be directly connected to the cathode 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. When the partition layer is formed of a metal material, the partition layer is in direct contact with the cathode auxiliary electrode 134, so the partition layers of adjacent light-emitting units 130 also need to be spaced apart.

[0062] Specifically, the cathode 133 further includes a cathode 133 redundant electrode, which is disposed on the partition structure 140, and the cathode 133 and the cathode 133 redundant electrode are disconnected by the partition structure 140. The cathode 133 redundant electrode is mainly the cathode 133 material evaporated onto the pixel definition layer 120 during the process of forming the cathode 133 on the entire surface, and the cathode 133 redundant electrode can be removed in the subsequent process, or it can be left there.

[0063] In order to avoid electrical connection between the cathode 133 and the redundant electrode of the cathode 133, it is also necessary to limit the thickness of the partition structure 140, so that the thickness h of the partition structure 140 is at least greater than or equal to 0.01um. Of course, the thickness of the partition structure 140 is also related to the thickness of the cathode 133. The thickness of the cathode 133 can generally be 100 angstroms to 300 angstroms (0.01um to 0.03um). In order to meet the requirements of the above-mentioned light transmittance and work function, in this case, the thickness h of the partition structure 140 should meet the requirements of greater than or equal to 0.01um and less than or equal to 0.06um. The main consideration of this implementation is that when the partition structure 140 is only used to isolate the cathode 133, the thickness h of the partition structure 140 does not need to exceed 0.06um. Specifically, the thickness of the partition structure 140 is greater than or equal to 0.02um and less than or equal to 0.05um, which has a better effect on isolating the cathode 133.

[0064] In another embodiment, the partition structure 140 is also used to sequentially separate one or more layers of the electron injection layer 1324, the electron transport layer 1321, the hollow blocking layer, the light-emitting layer 1322, the electron blocking layer 1326, the hole transport layer 1323 and the hole injection layer 1327 between the opening area 101 and the non-opening area 102 when the light-emitting functional layer 132 is deposited on the entire surface. However, considering that the thickness of the partition structure 140 required for multi-layer partition is relatively thick, it leads to instability in forming the partition structure 140 using a negative organic glue material. Therefore, further, considering that the electron transport layer 1321 in the light-emitting functional layer 132 is separated, the crosstalk problem between each light-emitting unit 130 can be reduced. The thickness of the partition structure 140 can be controlled so that the partition structure 140 can separate the cathode 133, the electron injection layer 1324 and the electron transport layer 1321. Among them, the thickness h of the partition structure 140 is greater than or equal to 0.02um and less than or equal to 0.15um. Specifically, when the thickness h of the partition structure 140 is greater than or equal to 0.04um and less than or equal to 0.1um, the partition effect on the cathode 133, the electron injection layer 1324 and the electron transport layer 1321 is better. It is worth mentioning that the anode 131 in this embodiment needs to adopt a whole-surface deposition process to form the whole-surface anode 131. When the thickness of the partition structure 140 is larger, the anode 131 will also be isolated. Therefore, the thickness of the partition structure 140 should not be too large, that is, less than or equal to 0.15um. Of course, the thicker the thickness of the partition structure 140, the stronger its isolation ability, which can make thicker film layers be isolated. When the anode 131 is also isolated, the thickness of the anode 131 can be increased to make part of the anode 131 isolated, but because the thickness of the anode 131 is sufficient, the anode 131 will not be completely isolated.

[0065] Figure 6 is a schematic diagram of the steps of the method for manufacturing the display panel of the present application, Figure 7is a schematic diagram of the manufacturing process of the display panel of the present application, see Figure 6 to Figure 7 As shown, the present application also discloses a method for manufacturing a display panel, comprising the steps of:

[0066] S110: providing a substrate;

[0067] S120: forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas;

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

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

[0070] S150: sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units;

[0071] The partition structure 140 is formed of a negative organic resin material, and the radial width of the partition structure 140 gradually decreases as the partition structure 140 approaches the base substrate 110 .

[0072] The present application forms the partition structure 140 by using a negative organic glue material. First, the negative organic glue material can form a partition structure 140 with a wide upper part and a narrow lower part during the exposure and development process. Secondly, the negative organic glue material has strong insulation properties. Even if the angle is not controlled during the deposition of the entire surface of the bottom electrode, the bottom electrode is in contact with the partition structure 140. The partition structure 140 can also play an insulating role to prevent the electrical crosstalk problem between the bottom electrodes of adjacent light-emitting units 130. The present application sets a partition structure 140. When the bottom electrode is formed in the light-emitting unit 130, the partition structure 140 is used to isolate the bottom electrodes of multiple light-emitting units 130, so that the bottom electrodes of multiple light-emitting units 130 are not connected to each other. In the process of forming 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 132 process can be directly carried out after the bottom electrode is deposited on the entire surface, thereby reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes active metal materials, the problems of 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 improved, and the display effect of the display panel 100 is improved.

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

[0074] Before step S120, the method further includes the following steps: forming a driving circuit layer 150 on the base substrate 110, wherein the driving circuit layer 150 includes a plurality of thin film transistors and driving circuits, and the thin film transistors and the driving circuits form a driving circuit for driving the plurality of light emitting units 130 to emit light. In the process of forming the driving circuit layer 150, a via hole is provided corresponding to the thin film transistor driving the light emitting unit 130, and the via hole is used to provide a cathode auxiliary electrode 134 connected between the thin film transistor and the cathode 133 of the light emitting unit 130.

[0075] The step S120 also includes the following steps:

[0076] S121: depositing a cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning;

[0077] S122: depositing and patterning a pixel definition layer on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

[0078] In this embodiment, after completing the process of the above-mentioned driving circuit layer 150, a cathode auxiliary electrode 134 is formed in the opening area 101, and at the via position of the driving circuit layer 150, the cathode auxiliary electrode 134 is connected to the output end of the thin film transistor to achieve voltage control of the cathode 133.

[0079] In one embodiment, the step S150 includes:

[0080] S151: Depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by a partition structure;

[0081] S152: depositing anodes on the entire surface to form a plurality of the light-emitting units.

[0082] In this solution, the light-emitting functional layer 132 of the light-emitting unit 130 is formed by the partition structure 140, and 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 arranged in sequence from the cathode 133 toward the anode 131. In this embodiment, the thickness of the partition structure 140 can be set so that the partition structure 140 cannot separate the anode 131, thereby forming a whole surface of the anode 131.

[0083] The present application forms the partition structure 140 by using a negative organic glue material. First, the negative organic glue material can form a partition structure 140 with a wide upper part and a narrow lower part during the exposure and development process. Secondly, the negative organic glue material has strong insulation properties. Even if the angle is not controlled during the deposition of the entire surface of the bottom electrode, the bottom electrode is in contact with the partition structure 140. The partition structure 140 can also play an insulating role to prevent the electrical crosstalk problem between the bottom electrodes of adjacent light-emitting units 130. The present application sets a partition structure 140. When the bottom electrode is formed in the light-emitting unit 130, the partition structure 140 is used to isolate the bottom electrodes of multiple light-emitting units 130, so that the bottom electrodes of multiple light-emitting units 130 are not connected to each other. In the process of forming 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 132 process can be directly carried out after the bottom electrode is deposited on the entire surface, thereby reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes active metal materials, the problems of 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 improved, and the display effect of the display panel 100 is improved.

[0084] It should be noted that the inventive concept of the present application can form a large number of embodiments, but the length of the application document is limited and it is impossible to list them one by one. Therefore, under the premise of no conflict, the embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effects will be enhanced.

[0085] The above content is a further detailed description of the present application in combination with specific optional implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A display panel, comprising a base substrate, a pixel definition layer and a light-emitting unit, wherein the pixel definition layer is disposed on the base substrate and has a plurality of opening areas, and the light-emitting unit is disposed on the base substrate and is located in the opening areas; characterized in that: The display panel further includes a partition structure, which is located in the non-opening area and is disposed on the pixel definition layer; The light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, wherein the bottom electrode is arranged on the substrate, the light-emitting functional layer is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer; The partition structure is used to partition the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited on the entire surface; The partition structure is formed of a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction in which the partition structure approaches the base substrate.

2. The display panel according to claim 1, characterized in that: 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 base substrate is the top surface, the side of the partition structure close to the base substrate is the bottom surface, 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.

3. The display panel according to claim 2, characterized in that: The thickness of the partition structure is greater than or equal to 0.01um and less than or equal to 0.06um; 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.

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

5. The display panel according to claim 1, characterized in that: The bottom electrode is a light-transmitting electrode, formed of one or both of magnesium material and silver material; the top electrode is formed of a reflective metal material, and a plurality of the 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 an anode, and the bottom electrode is a cathode; 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; the partition structure is used to separate the cathodes of two adjacent light-emitting units when the cathode is deposited on the entire surface.

6. The display panel according to claim 5, characterized in that: The display panel further includes a cathode auxiliary electrode, the cathode auxiliary electrode is formed of a transparent metal oxide material, the cathode auxiliary electrode is arranged under the cathode and is electrically connected to the cathode; The cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer.

7. The display panel according to claim 5, characterized in that: The cathode further comprises a cathode redundant electrode, the cathode redundant electrode is arranged on the partition structure, and the cathode and the cathode redundant electrode are disconnected by the partition structure; The partition structure is also used to sequentially separate the electron transport layer, the light emitting layer and the hole transport layer between the opening area and the non-opening area when the electron transport layer, the light emitting layer and the hole transport layer are deposited on the entire surface.

8. A method for manufacturing a display panel, characterized in that: Includes steps: Providing a substrate; forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas; forming a partition structure on the pixel definition layer; The bottom electrode material is deposited on the entire surface, and the partition structure is used to separate the bottom electrodes of two adjacent light-emitting units; Sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units; The partition structure is formed of a negative organic adhesive material, and the radial width of the partition structure gradually decreases from the direction in which the partition structure approaches the base substrate.

9. The method for manufacturing a display panel according to claim 8, characterized in that: The step of forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening areas includes: Depositing cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning; 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 a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

10. The method for manufacturing a display panel according to claim 8, characterized in that: The step of sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units includes: Depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by an overhanging structure; Depositing anodes on the entire surface to form a plurality of the light-emitting units; Wherein, the top electrode is an anode, and the bottom electrode is a cathode; 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; The cathode is formed of one or both of magnesium material and silver material, and is a light-transmitting electrode; the anode is formed of a reflective metal material, and multiple light-emitting units share the anode; and the light emitted by the light-emitting unit is emitted from one side of the substrate.

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