CN117241622A - Display panel and manufacturing method thereof - Google Patents

Abstract

The application provides a display panel and a manufacturing method thereof, wherein the display panel comprises: a substrate; a plurality of sub-pixels disposed on the substrate; the pixel limiting layer is arranged on the substrate and used for limiting the positions of the plurality of sub-pixels; the isolation structure is arranged on the pixel limiting layer and used for isolating a plurality of sub-pixels, and comprises a first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer which are sequentially stacked, wherein cathode layers of two adjacent sub-pixels are connected through the first conductive layer, a via hole is formed in the first insulating layer, and the first conductive layer and the second conductive layer are connected through the via hole; the cathode auxiliary layer is arranged on the isolation structure and is connected with the second conductive layer. By the method, uniformity of the whole cathode is improved, the area of the cathode is increased, IR Drop caused by larger cathode resistance is further weakened, and the phenomenon of uneven display brightness is improved.

Description

A display panel and its production method

Technical field

This application mainly relates to the field of display technology, and in particular to a display panel and its manufacturing method.

Background technique

OLED (Organic Light-Emitting Diode), that is, organic light-emitting diode, its self-luminous principle is to use ITO transparent electrode and metal electrode as the anode (Anode) and cathode (Cathode) of the device respectively. Under a certain voltage drive, electrons and holes From the cathode and anode respectively, they move to the organic light-emitting layer and combine to emit visible light. Because it does not require a backlight, has a large viewing angle, richer colors, and significant energy saving, it is widely used in various fields.

Among related technologies, in order to achieve high resolution and colorization of passive matrix OLEDs and better solve the problems of low cathode template resolution and low device yield, the cathode isolation pillar structure was introduced in actual research and FMM ( FineMetal Mask (Metal Mask) process is deposited, that is, no metal template is used in device preparation, but insulating partitions are made on the substrate before evaporating the organic film and metal cathode to ultimately separate different pixels of the device. On, implement pixel array.

Using the above method will cause the uniformity of the entire cathode to be poor, resulting in an obvious IR Drop (resistance voltage drop), and problems such as uneven brightness in the display.

Contents of the invention

The main purpose of this application is to propose a display panel and its manufacturing method, which can form an auxiliary cathode on the top of the cathode in the panel, connect the cathode to the auxiliary cathode, increase the cathode area, improve the uniformity of the entire cathode, and reduce IRDrop , improve the problem of uneven display brightness.

In order to solve the above problems, the present application provides a display panel, which includes the following structure: a substrate; a plurality of sub-pixels arranged on the substrate; a pixel defining layer arranged on the substrate, and the pixel defining layer is used to define the pixels of the multiple sub-pixels. position; the isolation structure is provided on the pixel defining layer. The isolation structure is used to isolate multiple sub-pixels. The isolation structure includes a first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer stacked in sequence. Two adjacent layers The cathode layer of the sub-pixel is connected through the first conductive layer, the first insulating layer is provided with a via hole, the first conductive layer and the second conductive layer are connected through the via hole; the cathode auxiliary layer is provided on the isolation structure, and the cathode auxiliary layer is connected second conductive layer.

In one embodiment, the first insulating layer includes a main body and a top disposed on the main body. The top extends out of the upper surface of the main body to form a first overhang; the second insulating layer extends out of the upper surface of the second conductive layer. to form a second overhang.

In one embodiment, the via holes extend through the main body and the top.

In one embodiment, the cathode auxiliary layer covers the upper surface, side surfaces, and lower surfaces of the second overhang portion, the side surfaces of the second conductive layer, and the upper surface and side surfaces of the first overhang portion.

In one embodiment, an organic layer is further provided on the side of the first overhanging portion, and the cathode auxiliary layer covers the organic layer.

In one embodiment, the sub-pixel includes an anode layer, a luminescent layer and a cathode layer stacked in sequence, the luminescent layer overlaps the upper surface of the pixel defining layer, and the cathode layer extends between the luminescent layer and the first conductive layer and contacts the pixel defining layer. the upper surface of the layer.

In one embodiment, the display panel further includes: a protective layer covering the cathode layer, the first conductive layer, the first insulating layer, and the cathode auxiliary layer; a first encapsulation layer covering the protective layer and the second insulation layer layer, the upper surface of the first encapsulation layer is a flat structure; the second encapsulation layer is disposed on the first encapsulation layer.

In order to solve the above problems, the present application also provides a method for manufacturing a display panel. The steps of the manufacturing method include: providing a substrate; forming an anode layer and a pixel defining layer on the substrate; and sequentially forming a first conductive layer on the pixel defining layer. , a first insulating layer, a second conductive layer and a second insulating layer, the first insulating layer is provided with a via hole, the first conductive layer and the second conductive layer are connected through the via hole; a light-emitting layer is formed on the anode layer in sequence and a cathode layer, and a cathode auxiliary layer is formed on the isolation structure, the cathode auxiliary layer is connected to the second conductive layer, the anode layer, the light-emitting layer and the cathode layer form a sub-pixel, and the cathode layers of two adjacent sub-pixels are connected through the first conductive layer.

In one embodiment, forming the first conductive layer, the first insulating layer, the second conductive layer and the second insulating layer on the pixel defining layer in sequence includes: forming the first conductive layer and the first insulating layer on the pixel defining layer in sequence. layer, the first insulating layer includes a main body part and a top part disposed on the main body part, the top part extends from the upper surface of the main body part to form a first overhang part; a via hole penetrating the main body part and the top part is formed on the first insulating layer; A second conductive layer is formed on the first insulating layer, and the second conductive layer is connected to the first conductive layer through a via hole; a second insulating layer is formed on the second conductive layer, and the second insulating layer extends out of the upper surface of the second conductive layer. A second overhang is formed.

In one embodiment, sequentially forming a luminescent layer and a cathode layer on the anode layer, and forming a cathode auxiliary layer on the isolation structure includes: forming a luminescent layer on the anode layer, and forming an organic layer on the side of the first overhang; A cathode layer is formed on the light-emitting layer, and a cathode auxiliary layer is formed on the upper surface, side surfaces, and lower surfaces of the second overhanging portion, the side surfaces of the second conductive layer, and the upper surface and side surfaces of the first overhanging portion.

Through the above display panel and the display panel made by the above manufacturing method, a double suspension structure is added to the suspension structure base, so that the cathode forms an auxiliary cathode on the top suspension structure, so that the bottom cathode and the auxiliary cathode are connected through the metal pillar, thereby It improves the uniformity of the entire cathode, increases the area of the cathode, thereby reducing the cathode resistance, thereby weakening the IR Drop caused by the large cathode resistance to improve the uneven display brightness.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts. in:

Figure 1 is a schematic structural diagram of an embodiment of a display panel provided by this application;

Figure 2 is an intermediate structural schematic diagram of an embodiment of a display panel provided by this application;

Figure 3 is a top view of the positions of the anode, cathode, and auxiliary cathode of the backplate;

Figure 4 is a schematic flow chart of an embodiment of a display panel manufacturing method provided by this application;

Figure 5 is a schematic flowchart of the sub-steps of step S14 in Figure 4;

Figure 6 is a schematic flowchart of the sub-steps of step S16 in Figure 4;

Figures 7a to 7k are structural schematic diagrams corresponding to each step in the display panel manufacturing method provided in Figure 4;

FIG. 8 is a schematic structural diagram of an embodiment of a display device provided by this application.

Reference signs: 100, display panel; 10, substrate; 20, sub-pixel; 21, anode layer; 22, light-emitting layer; 23, cathode layer; 30, pixel defining layer; 40, isolation structure; 41, first conductive layer ; 42. First insulating layer; 421. Main body; 422. Top; 43. Second conductive layer; 44. Second insulating layer; 50. Cathode auxiliary layer; 60. Protective layer; 70. First packaging layer; 80 , the second encapsulation layer; a, the first overhang part; b, the second overhang part; c, organic layer; A, via hole; 1, anode area; 2, cathode area; 3, auxiliary cathode area; 200, display device .

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. It can be understood that the specific embodiments described here are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for convenience of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

The terms "first", "second", etc. in this application are used to distinguish different objects, rather than describing a specific sequence. Furthermore, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes Other steps or units inherent to such processes, methods, products or devices.

Reference herein to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

At present, in order to better solve the problems of low cathode template resolution and low device yield, the cathode isolation pillar structure is introduced in actual research to isolate different pixels and solve problems such as short circuit of the organic light-emitting layer between adjacent pixels. In actual design, the opening spacing between pixels is small and the width of the pendant is limited. Therefore, the width of the conductive oxide cylinder is small and the contact resistance is large, resulting in poor uniformity of the entire cathode. The resulting IR Drop is obvious, and problems such as uneven brightness appear on the display.

Referring to Figures 1 and 2, Figure 1 is a schematic structural diagram of an embodiment of a display panel provided by the present application. FIG. 2 is a schematic structural diagram of an embodiment of a display panel provided by this application. The display panel includes: a substrate 10, a sub-pixel 20, a pixel defining layer 30, an isolation structure 40, and a cathode auxiliary layer 50.

Specifically, a plurality of sub-pixels 20 are provided on the substrate 10. The sub-pixels 20 include an anode layer 21, a light-emitting layer 22 and a cathode layer 23 stacked in sequence; a pixel defining layer 30 is provided on the substrate 10, and the pixel defining layer 30 is used to Define the positions of the plurality of sub-pixels 20; the isolation structure 40 is provided on the pixel definition layer. The isolation structure 40 is used to isolate the plurality of sub-pixels 20. The isolation structure 40 includes a first conductive layer 41, a first insulating layer 42, and a first layer 42 stacked in sequence. Two conductive layers 43 and a second insulating layer 44, the cathode layers 23 of two adjacent sub-pixels 20 are connected through the first conductive layer 41, the first insulating layer 42 is provided with a via A, the first conductive layer 41 and the second conductive layer The layers 43 are connected through via holes; the cathode auxiliary layer 50 is provided on the isolation structure 40, and the cathode auxiliary layer 50 is connected to the second conductive layer 43.

Among them, the first conductive layer 41 and the second conductive layer 43 can be made of metal oxide, transition metal oxide or other conductive materials; specifically, the materials of the first conductive layer 41 and the second conductive layer 43 can be the same. Not the same, the specific setting should be based on the actual situation.

Optionally, in one embodiment, the first insulating layer 42 includes a main body part 421 and a top part 422 disposed on the main body part 421. The top part 422 extends from the upper surface of the main body part 421 to form a first overhang part a; a second The insulating layer 44 extends out of the upper surface of the second conductive layer 43 to form a second overhang b. Among them, the structures of the main body 421 and the top 422 of the first insulating layer 42 are respectively made of silicon monoxide (SiO), silicon dioxide (SiO2), silicon nitride (SiNx), silicon oxynitride (SiNO) and other materials, using different materials. The materials are etched at different rates to form an inverted trapezoidal mushroom shape. In one embodiment, the first insulating layer 42 adopts a double-layer structure of silicon monoxide (SiO) and silicon nitride (SiNx) to form a first overhang a above the first conductive layer 41 to form a first inverted trapezoid mushroom. -like structure; the second insulating layer 44 uses inorganic SiNx material to form a second overhang b above the second conductive layer 43 to form a second inverted trapezoidal mushroom-shaped structure. The first inverted trapezoidal structure and the second inverted trapezoidal structure are formed together. Double overhang construction.

Optionally, in one embodiment, the lengths of the first overhanging portion a and the second overhanging portion b are equal. In another embodiment, the length of the first overhanging portion a is smaller than the length of the second overhanging portion b. By constructing The manner of the first overhanging portion a and the second overhanging portion b causes the isolation structure 40 to exhibit a mushroom body structure to solve the problem of short circuit of the organic light-emitting layer between adjacent pixels.

Optionally, in one embodiment, the via A penetrates the main body part 421 and the top part 422, and the first insulating layer 42 is etched and punched to realize subsequent conductive processing of the bottom first conductive layer 41 and the top second conductive layer 42. Layer 43 is connected through via A, and the second conductive layer 43 is connected to the cathode auxiliary layer 50, and the first conductive layer 41 is connected to the cathode layer 23, thereby achieving connection and conduction between the four, forming a cathode conduction on the entire surface. .

Optionally, in one embodiment, the cathode auxiliary layer 50 covers the upper surface, side surfaces and lower surfaces of the second overhang part b, the side surfaces of the second conductive layer 43, and the upper surface and side surfaces of the first overhang part a.

Optionally, in one embodiment, an organic layer c is further provided on the side of the first overhang a, and the cathode auxiliary layer 50 covers the organic layer c.

During the evaporation deposition process, due to the existence of the extended overhang in the isolation structure 40, the cathode layer 23 and the luminescent layer 22 may break during the formation process of the extended overhang, so that the overhang is The cathode auxiliary layer 50 and the organic layer c are formed thereon. Specifically, in one embodiment, the cathode auxiliary layer 50 and the organic layer c are formed by changing the evaporation deposition angle of the cathode layer 23 and the light-emitting layer 22 so that they are broken at the second overhang b of the second insulating layer 44 , wherein the organic layer c covers part of the upper surface and side surfaces of the first overhanging portion a in the first insulating layer 42; the cathode auxiliary layer 50 covers the upper surface and side surfaces of the first overhanging portion a in the first insulating layer 42 and The upper surface and side surfaces of the second overhang b in the second insulating layer 44 cover the surface of the organic layer c, and are deposited and covered on the side surfaces of the second conductive layer 43 to be in contact with the second conductive layer 43 to form a cathode auxiliary layer. 50 and the second conductive layer 43.

Optionally, in one embodiment, the sub-pixel 20 includes an anode layer 21, a luminescent layer 22 and a cathode layer 23 stacked in sequence. The luminescent layer 22 overlaps the upper surface of the pixel defining layer 30, and the cathode layer 23 extends to the luminescent layer. 22 and the first conductive layer 41 and in contact with the upper surface of the pixel defining layer 30 . Due to the above-mentioned first overhang a and second overhang b, during the deposition of the cathode layer 23 and the luminescent layer 22 , the cathode layer 23 covers the upper surface and side surfaces of the luminescent layer 22 and is in contact with the first conductive layer 41 connection, thereby achieving conduction between the cathode layer 23 and the first conductive layer 41, and isolating the light-emitting layer 22 from the first conductive layer 41 through the cathode layer 23, preventing the light-emitting layer 22 from being conductive with the first conductive layer 41, so as to The problem of short-circuiting the organic light-emitting layer between adjacent sub-pixels occurs.

There are multiple sub-pixels 20 and are spaced between the isolation structures 40. The material of the anode layer 21 includes but is not limited to chromium, titanium, gold, silver, copper, aluminum, ITO, combinations thereof or other suitable conductive materials. its combination.

The light-emitting layer 22 is used to emit red light, blue light or green light when energized. The light-emitting layer 22 may include one of HIL (Hole Injection Layer, hole injection layer), HTL (Hole Transfer Layer, hole transport layer), EML (Emitting Layer, emission layer), and ETL (Electron Transfer Layer, electron transfer layer). or more.

Both ends of the cathode layer 23 are in contact with the first conductive layer 41 in the isolation structure 40, so that adjacent sub-pixels connect the cathode layers 23 of each other through the first conductive layer 41 to achieve cathode connection across the entire surface. The material of the cathode layer 23 includes but is not limited to chromium, titanium, gold, silver, copper, aluminum, ITO, combinations thereof or other suitable conductive materials and combinations thereof. The material of the cathode layer 23 may be the same as the material of the anode layer 21 , or may be different, and is specifically set according to the actual situation.

Specifically, in one embodiment, the above-mentioned cathode auxiliary layer 50 is as shown in Figure 3. Figure 3 is a top view of the positions of the anode, cathode and auxiliary cathode of the backplane. The middle position is the anode area 1, the open cathode area 2 is connected to the entire surface through the conductive layer of the overhang structure around the anode, and the auxiliary cathode area 3 at the top of the overhang structure forms an annular entire surface conductive layer around each opening, and is connected to the top conductive layer The overlapping connection realizes the connection surface of the entire auxiliary cathode, thereby improving the reliability of the overlapping connection over the entire surface.

Optionally, in an embodiment, as shown in FIG. 1 , the display panel further includes: a protective layer 60 , a first encapsulation layer 70 and a second encapsulation layer 80 . The protective layer 60 covers the cathode layer 23 and the first conductive layer 41 , the first insulating layer 42, the cathode auxiliary layer 50; the first encapsulation layer 70 covers the protective layer 60 and the second insulating layer 44, the upper surface of the first encapsulation layer 70 is a flat structure; the second encapsulation layer 80 is provided on the first encapsulation On level 70.

Among them, after a single sub-pixel is formed through a single etching, the single-color OLED material and cathode are encapsulated and protected using inorganic packaging to form an etching protective layer, and then other light-emitting layers and cathodes are prepared one by one. In the three-color After both the light-emitting layer and the cathode are prepared, they are integrally packaged in the form of organic packaging or inorganic packaging. In one embodiment, the protective layer 60 uses inorganic packaging, the first packaging layer 70 uses organic packaging, and the second packaging layer 80 uses Inorganic packaging.

Optionally, in an embodiment, the protective layer 60 , the first encapsulation layer 70 and the second encapsulation layer 80 may adopt any encapsulation material, such as inorganic encapsulation, organic encapsulation and inorganic-organic composite encapsulation, wherein, inorganic-organic composite encapsulation The material combines the advantages of good water and oxygen barrier properties of inorganic packaging materials and good film-forming properties of organic packaging materials.

This application also provides a manufacturing method of the display panel 100 to solve the above problems. The manufacturing method specifically includes the following steps:

Referring to Figure 4 and Figures 7a to 7k, Figure 4 is a schematic flow chart of an embodiment of a display panel manufacturing method provided by the present application. Figures 7a to 7k are schematic structural diagrams corresponding to each step in the display panel manufacturing method provided in Figure 4.

Step S10: Provide a substrate.

Specifically, the substrate 10 plays a supporting role in the entire display panel and is used to carry various components and materials.

Optionally, in one embodiment, the substrate 10 includes a substrate (not shown) and a driving circuit (not shown), and the display panel 100 is an active OLED; in another embodiment, the substrate only includes a substrate. , excluding the driving circuit, the display panel 100 is a passive OLED.

Specifically, in one embodiment, the material of the substrate is a glass substrate, and the glass substrate is generally used as a carrier; in another embodiment, the material of the substrate is a flexible substrate, wherein the flexible substrate is Flexible PI (polyimide) film serves as the substrate.

The above drive circuits can be divided into pixel drive circuits and peripheral drive circuits. The pixel drive circuit mainly provides conditions for continuous lighting of the panel, while the peripheral circuits provide accurate input signals for the matrix circuit of the panel. For example, For example, the active matrix circuit is provided with row-by-row scanning signals (row driving signals), and data signals (column driving signals) with display information are provided for each OLED pixel in the selected row. Therefore, the pixel drive circuit and the peripheral drive circuit complement each other and work closely together to complete the normal operation of driving the active OLED display.

Step S12: Form an anode layer and a pixel defining layer on the substrate.

Specifically, as shown in Figure 7a, a corresponding required metal layer is formed on the substrate as the anode layer material, wherein the material of the metal layer includes but is not limited to chromium, titanium, gold, silver, copper, aluminum, ITO, and others. or other suitable conductive materials and combinations thereof.

Optionally, in one embodiment, as shown in FIG. 7a , by coating a first layer of photoresist on the metal layer and patterning the photoresist, the corresponding required structure is retained to form the required structure on the substrate. The anode layer 21; prepare a pixel defining layer 30 above the etched anode layer 21 to isolate the anode layer 21 of adjacent sub-pixels 20. Similarly, apply a second layer of photolithography on top of the pixel defining layer 30. Glue and pattern the photoresist to retain the corresponding required structure to form the pixel definition layer 30; in one embodiment, the height of the pixel definition layer 30 perpendicular to the direction of the substrate is higher than the anode layer 21. Among them, the pixel defining layer 30 uses organic materials including but not limited to polyimide, and the inorganic materials of the pixel defining layer 30 include but are not limited to silicon oxide (SiO2), silicon nitride (Si3N4), silicon oxynitride (Si2N2O), fluorine Magnesium oxide (MgF2) or their combination. In another embodiment, a PDL material is used as the material of the pixel defining layer 30. PDL is a pixel defining material used to define each sub-pixel so that colors between the light-emitting layers therein do not interfere with each other.

The etching method includes wet etching or dry etching, wherein dry etching includes laser etching or plasma etching. Wet etching includes chemical etching.

Step S14: Form a first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer on the pixel defining layer in sequence, with via holes provided on the first insulating layer, the first conductive layer and the second conductive layer. The layers are connected via vias.

Refer to Figure 5, which is a schematic flowchart of the sub-steps of step S14 in Figure 4.

The sub-steps of step S14 specifically include the following steps:

Step S140: Form a first conductive layer and a first insulating layer on the pixel defining layer in sequence. The first insulating layer includes a main body and a top disposed on the main body. The top extends from the upper surface of the main body to form a first overhang. .

Optionally, in one embodiment, as shown in FIG. 7b , a conductive layer is deposited on the pixel defining layer 30 using physical vapor deposition, chemical vapor deposition or vacuum sputtering, and a third layer of light is coated on the conductive layer. Resist and pattern the photoresist to retain the structure of the first conductive layer 41 on the pixel defining layer, where the material of the first conductive layer 41 is made of metal oxide or transition metal oxide or other conductive materials, such as metal Materials such as molybdenum (MO) and aluminum nitride (AlN).

Optionally, in an embodiment, as shown in FIG. 7c, a first insulating layer 42 is prepared above the first conductive layer 41, and by utilizing the difference in etching rates of different materials, the first insulating layer 42 is formed on the first insulating layer 42. A first overhang part a is formed to form an overhang structure. The material of the first insulating layer 42 may be a non-conductive organic material, and the non-conductive organic material includes a negative photosensitive organic material. For example, negative photosensitive organic materials include, but are not limited to, negative photoresists.

Optionally, in an embodiment, the first overhang structure composed of the first insulating layer 42 can be polymerized and cross-linked by polymerizing and cross-linking the illuminated portion of the negative photoresist during the exposure process, and the unilluminated portion is not. Cross-linking polymerization occurs. The surface of the negative photoresist is more likely to be polymerized and cross-linked. The light intensity of the negative photoresist away from the surface gradually weakens. The negative photoresist is polymerized and cross-linked from the surface to the direction away from the surface. The degree gradually weakened. During the development process, the negative photoresist that has not undergone cross-linking and polymerization will be washed away, resulting in an overhanging structure with an inverted trapezoidal structure.

Step S142: Form a via hole penetrating the main body and the top of the first insulating layer.

Optionally, in an embodiment, as shown in FIG. 7d , etching or other methods can be used to form a via A on the first insulating layer 42 , and the subsequent second conductive layer 43 and the first conductive layer are connected through the via A. 41 for connection, increasing the number of overlapping interfaces between the cathode and the auxiliary cathode, and improving the reliability of the overlapping interface.

Step S144: Form a second conductive layer on the first insulating layer, and connect the second conductive layer to the first conductive layer through the via hole.

Optionally, in one embodiment, as shown in FIG. 7e , a conductive layer is deposited on the first insulating layer 42 where the via A is formed by physical vapor deposition, chemical vapor deposition or vacuum sputtering to form a third insulating layer. Two conductive layers 43, the second conductive layer 43 overlaps with the bottom first conductive layer 41 through the via hole A. In one embodiment, considering the slope angle of cathode evaporation deposition, the width of the second conductive layer 43 should be smaller than or equal to the first conductive layer 41 in cross-section.

Step S146: Form a second insulating layer on the second conductive layer, and the second insulating layer extends out of the upper surface of the second conductive layer to form a second overhang.

Optionally, in one embodiment, as shown in FIG. 7f , a second insulating layer 44 is formed above the second conductive layer 43 by deposition or other methods, wherein the second insulating layer 44 is formed in the same manner as the first insulating layer. 42 is formed in the same way and will not be repeated here. In one embodiment, the length of the second overhanging portion b of the second insulating layer 44 is equal to the length of the first overhanging portion a of the first insulating layer 42 .

Step S16: Form a luminescent layer and a cathode layer on the anode layer in sequence, and form a cathode auxiliary layer on the isolation structure. The cathode auxiliary layer is connected to the second conductive layer. The anode layer, luminescent layer and cathode layer form a sub-pixel, and two adjacent sub-pixels are formed. The cathode layers of the pixels are connected through the first conductive layer.

Refer to Figure 6, which is a schematic flowchart of the sub-steps of step S16 in Figure 4.

The sub-steps of step S16 specifically include the following steps:

Step S160: Form a light-emitting layer on the anode layer, and form an organic layer on the side of the first overhang.

Specifically, since the colors of light emitted by different sub-pixels 20 are different, the materials of the light-emitting layers 22 in different sub-pixels 20 are different, and the sub-pixels 20 that emit light of different colors need to be manufactured in different steps. The light-emitting layer 22 includes, but is not limited to, a red light-emitting layer (not shown), a green light-emitting layer (not shown), and a blue light-emitting layer (not shown). Among them, the specific order of forming the red luminescent layer, the green luminescent layer and the blue luminescent layer is set according to the actual situation. For example, a red light-emitting layer is formed first, then a green light-emitting layer, and finally a blue light-emitting layer.

Optionally, in one embodiment, as shown in FIG. 7g , the luminescent layer 22 is formed by evaporation deposition. However, due to the first overhanging portion a and the second overhanging portion b of the overhanging structure, the luminescent layer 22 is formed by evaporation deposition. The film layer breaks at the protruding part, so that the light-emitting layer at the lower break surface overlaps the pixel defining layer 30 but is not in contact with the first conductive layer 41 , and the upper break surface is at the first edge of the first insulating layer 42 An organic layer c is formed at the overhanging portion a.

Step S162: Form a cathode layer on the light-emitting layer, and form a cathode auxiliary layer on the upper surface, side surfaces and lower surfaces of the second overhanging part, the side surfaces of the second conductive layer, and the upper surface and side surfaces of the first overhanging part.

Optionally, in one embodiment, as shown in FIG. 7h , the cathode layer 23 and the cathode auxiliary layer 50 are formed above the light-emitting layer 22 by evaporation deposition. The same reason as the formation of the light-emitting layer 22 is due to the first overhang part a and the second overhang part b of the protruding parts of the overhang structure, causing the cathode to have film layer breakage in the protruding part. In one embodiment, by changing the evaporation angle , so that the cathode wraps the luminescent layer 22 at the lower break, so that the luminescent layer 22 is isolated from the first conductive layer 41, and the cathode layer 23 is directly connected to the first conductive layer 41, so that the cathode layer 23 of different sub-pixels 20 can pass through The first conductive layer 41 is connected to form a network connection of cathodes between different sub-pixels, wherein the first conductive layer 41 is higher than the cathode layer 23 in a direction perpendicular to the substrate. The cathode at the upper break is deposited along the double overhang structure constructed by the first insulating layer 42 and the second insulating layer 44, so that on the upper surface, side and lower surface of the second overhang b, the side of the second conductive layer 43 , and the upper surface and side surfaces of the first overhang a form a cathode auxiliary layer 50, and the cathode auxiliary layer 50 overlaps and conducts with the side surfaces of the second conductive layer 43, thereby realizing the cathode auxiliary layer 50 and the second conductive layer 43, The overall conduction of the first conductive layer 41 and the cathode layer 23 increases the reliability of the cathode connection, effectively reduces the overall resistance of the cathode, thereby improving the uniformity of the entire cathode.

Optionally, in one embodiment, the above preparation method also includes packaging the display panel. As shown in Figure 7i, the monochromatic OLED material and cathode are first protected by packaging, and then other light-emitting layers and cathodes are prepared one by one, such as As shown in Figure 7j and Figure 7k, after the three-color organic light-emitting layer and the cathode have been patterned and prepared, they are integrally packaged using a combination of organic packaging and inorganic packaging. The protective layer 60 uses inorganic packaging. The first packaging The layer 70 adopts organic encapsulation, and the second encapsulation layer 80 adopts inorganic encapsulation.

This application provides a display panel. Through the above display panel and the display panel made by the above manufacturing method, a double suspension structure is added to the suspension structure base, so that the cathode forms a mesh-shaped auxiliary cathode on the top suspension structure, so that the bottom cathode and the auxiliary cathode are connected through metal pillars , thus improving the uniformity of the entire cathode, increasing the area of the cathode to reduce the cathode resistance, thereby weakening the IR Drop caused by the large cathode resistance, so as to improve the uneven display brightness.

Refer to FIG. 8 , which is a schematic structural diagram of an embodiment of a display device provided by the present application. The display device 200 includes any of the display panels 100 introduced in the above embodiments or the display panel 100 manufactured by the above manufacturing method, so as to provide stable image output to the display device 200 through the display panel 100 .

The embodiments of the present application have been introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and the core idea of the present application; at the same time, for Those skilled in the art may make changes in the specific implementation and application scope based on the ideas of the present application. In summary, the contents of this description should not be understood as limiting the present application.

Claims (10)

1. A display panel, characterized in that it includes: substrate; A plurality of sub-pixels arranged on the substrate; A pixel definition layer, provided on the substrate, the pixel definition layer is used to define the positions of a plurality of the sub-pixels; An isolation structure is provided on the pixel defining layer. The isolation structure is used to isolate a plurality of the sub-pixels. The isolation structure includes a first conductive layer, a first insulating layer, a second conductive layer and a third layer that are stacked in sequence. Two insulating layers, the cathode layers of two adjacent sub-pixels are connected through the first conductive layer, the first insulating layer is provided with a via hole, and the first conductive layer and the second conductive layer pass through The via hole connection; A cathode auxiliary layer is provided on the isolation structure, and the cathode auxiliary layer is connected to the second conductive layer. 2. The display panel according to claim 1, wherein the first insulating layer includes a main body part and a top part disposed on the main body part, and the top part extends from an upper surface of the main body part to form a first pendant part; The second insulating layer extends beyond the upper surface of the second conductive layer to form a second overhang. 3. The display panel according to claim 2, wherein the via hole penetrates the main body part and the top part. 4. The display panel according to claim 2, wherein the cathode auxiliary layer covers the upper surface, side surfaces and lower surface of the second overhang, the side surfaces of the second conductive layer, and the third The upper surface and sides of an overhang. 5. The display panel according to claim 4, wherein an organic layer is further provided on the side of the first overhanging portion, and the cathode auxiliary layer covers the organic layer. 6. The display panel according to claim 1, wherein the sub-pixels include an anode layer, a luminescent layer and a cathode layer stacked in sequence, and the luminescent layer overlaps the upper surface of the pixel defining layer, so The cathode layer extends between the light-emitting layer and the first conductive layer and contacts the upper surface of the pixel defining layer. 7. The display panel according to claim 6, wherein the display panel further comprises: Protective layer, the protective layer covers the cathode layer, the first conductive layer, the first insulating layer, and the cathode auxiliary layer; A first encapsulation layer, the first encapsulation layer covers the protective layer and the second insulating layer, and the upper surface of the first encapsulation layer is a flat structure; A second encapsulation layer is provided on the first encapsulation layer. 8. A method of manufacturing a display panel, characterized by comprising: providing a substrate; forming an anode layer and a pixel defining layer on the substrate; A first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer are formed on the pixel defining layer in sequence, the first insulating layer is provided with a via hole, the first conductive layer and the The second conductive layer is connected through the via hole; A luminescent layer and a cathode layer are formed on the anode layer in sequence, and a cathode auxiliary layer is formed on the isolation structure. The cathode auxiliary layer is connected to the second conductive layer. The anode layer, the luminescent layer and the The cathode layer forms a sub-pixel, and the cathode layers of two adjacent sub-pixels are connected through the first conductive layer. 9. The method of manufacturing a display panel according to claim 8, wherein a first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer are sequentially formed on the pixel defining layer, include: A first conductive layer and a first insulating layer are sequentially formed on the pixel defining layer. The first insulating layer includes a main body part and a top part disposed on the main body part. The top part extends out of the upper part of the main body part. surface to form a first overhang; forming a via hole penetrating the main body part and the top part on the first insulating layer; forming a second conductive layer on the first insulating layer, and the second conductive layer is connected to the first conductive layer through the via hole; A second insulating layer is formed on the second conductive layer, and the second insulating layer extends out of the upper surface of the second conductive layer to form a second overhang. 10. The method for manufacturing a display panel according to claim 9, wherein forming a light-emitting layer and a cathode layer on the anode layer in sequence, and forming a cathode auxiliary layer on the isolation structure includes: forming a light-emitting layer on the anode layer and forming an organic layer on the side of the first overhang; A cathode layer is formed on the light-emitting layer, and a cathode is formed on the upper surface, side and lower surface of the second overhang, the side of the second conductive layer, and the upper surface and side of the first overhang. Auxiliary layer.