Display panel and manufacturing method thereof, and display device

Abstract

The present application provides a display panel and a method for preparing the same, as well as a display device. The display panel includes: a driving substrate; a pixel definition layer; a conductive isolation structure, which is protruding from the pixel definition layer and surrounds a pixel opening; a sub-pixel unit, including a first electrode, a light-emitting layer, and a second electrode stacked in the pixel opening, the second electrode being in contact with and conductive with the conductive isolation structure. The light-emitting layer includes at least two stacked light-emitting units, and a connecting layer is provided between every two adjacent light-emitting units; the connecting layer includes a metal spacer layer; an isolation layer is also provided in the pixel opening, the isolation layer is provided on the pixel definition layer, and extends along the pixel definition layer toward the conductive isolation structure and beyond the edge of the light-emitting unit between the first electrode and the metal spacer layer to be exposed, the isolation layer and the metal material repel each other, so that the metal spacer layer and the conductive isolation structure are spaced apart from each other. The display panel improves display brightness and product yield.

Description

Technical Field

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

[0002] In the field of display technology, organic light emitting diode (OLED) display devices are widely used in many fields such as flat panel displays, flexible displays, automotive displays and solid-state lighting due to their advantages such as wide color gamut, high contrast, energy saving and foldability.

[0003] As users have higher and higher requirements for display brightness and life, the tandem OLED device structure has emerged. At the same time, various new technologies are constantly being researched and developed. Among them, eLEAP technology is most likely to become one of the new technologies in the future because it can remove the high-precision metal mask (FMM) for evaporation and can increase the pixel opening rate and pixel density, greatly improving the brightness and service life of the product.

[0004] However, the combination of eLEAP technology and tandem OLED device structure makes the technical preparation process more complicated. It is easy for the organic film layer to be too thin at the edge of the conductive isolation structure, or for the metal spacer layer in the connecting layer of the OLED tandem device to be too large due to alignment deviation. At the same time, the metal spacer layer is rough and will diffuse under large current, which can easily lead to the metal spacer layer contacting the conductive isolation structure and causing series connection with the second electrode, affecting the product yield. Summary of the invention

[0005] The present application provides a display panel and a method for preparing the same, and a display device, aiming to solve the problem in the prior art of combining the eLEAP technology with a tandem OLED device structure, in which a metal spacer layer in the tandem OLED device contacts with a conductive isolation structure, causing it to be connected in series with a second electrode.

[0006] In order to solve the above technical problems, the first technical solution provided by the present application is to provide a display panel. The display panel includes:

[0007] Driver substrate;

[0008] A pixel definition layer is disposed on the driving substrate and has a plurality of pixel openings;

[0009] A conductive isolation structure protrudes from the pixel definition layer and surrounds the pixel opening;

[0010] The sub-pixel unit comprises a first electrode, a light-emitting layer and a second electrode stacked in a pixel opening; the second electrode is in contact with and connected to the conductive isolation structure;

[0011] The light-emitting layer includes at least two stacked light-emitting units, and a connecting layer is provided between every two adjacent light-emitting units; the connecting layer includes a metal spacer layer;

[0012] An isolation layer is also provided in the pixel opening. The isolation layer is arranged on the pixel definition layer and extends along the pixel definition layer toward the conductive isolation structure and beyond the edge of the light-emitting unit located between the first electrode and the metal isolation layer to be exposed. The isolation layer and the metal material repel each other so that the metal isolation layer and the conductive isolation structure are spaced apart from each other.

[0013] In some embodiments, the first electrode includes a metal material and the isolation layer includes a cathode patterning material.

[0014] In some embodiments, the isolation layer extends to the conductive isolation structure; the light-emitting layer includes a first light-emitting unit and a second light-emitting unit that are stacked, and the first light-emitting unit is disposed between the first electrode and the connecting layer;

[0015] The connection layer includes an N-type doped layer, a metal spacer layer and a P-type doped layer stacked in sequence;

[0016] The isolation layer extends along the pixel definition layer toward the conductive isolation structure and exceeds the edge of the first light emitting unit and the N-type doping layer to be exposed, so that the metal isolation layer and the conductive isolation structure are spaced apart from each other;

[0017] The second light-emitting unit at least covers the connecting layer, so that the metal spacing layer and the second electrode are spaced apart from each other.

[0018] In some embodiments, the isolation layer extends along the pixel definition layer and has a gap with the conductive isolation structure; the second electrode covers the second light-emitting unit and extends to the gap to be in contact with and electrically connected to the conductive isolation structure; or,

[0019] The isolation layer extends along the pixel definition layer and contacts the conductive isolation structure. The second electrode covers the second light emitting unit and the isolation layer and is electrically connected to the conductive isolation structure.

[0020] In some embodiments, the isolation layer is spaced apart from a side of the first electrode that is close to each other;

[0021] Wherein, the isolation layer covers part of the side wall surface of the pixel definition layer and the upper surface of the pixel definition layer, and extends along the upper surface to the conductive isolation structure; or,

[0022] The isolation layer only covers the upper surface of the pixel definition layer and extends along the upper surface to the conductive isolation structure.

[0023] In order to solve the above technical problems, the second technical solution provided by the present application is to provide a method for preparing a display panel. The preparation method comprises:

[0024] A prefabricated board is provided; the prefabricated board comprises a driving substrate, a first electrode, a pixel definition layer and a conductive isolation structure; wherein the first electrode and the pixel definition layer are arranged on the driving substrate, the pixel definition layer has a plurality of pixel openings, and the first electrode is located in the pixel openings; the conductive isolation structure protrudes from the pixel definition layer and surrounds the pixel openings;

[0025] An isolation layer is fabricated on the prefabricated board; the isolation layer is located on the pixel definition layer in the pixel opening and extends along the pixel definition layer toward the conductive isolation structure, and the isolation layer and the metal material repel each other;

[0026] A light-emitting layer is fabricated on the prefabricated board; the light-emitting layer comprises at least two light-emitting units stacked in a pixel opening, and a connection layer is disposed between every two adjacent light-emitting units, the connection layer comprising a metal spacer layer; wherein the light-emitting unit between the first electrode and the metal spacer layer is located in a region surrounded by an outer edge of the isolation layer, so that a side of the isolation layer close to the conductive isolation structure is exposed, and the metal spacer layer is spaced from the conductive isolation structure;

[0027] A second electrode is made on the light-emitting layer; the second electrode pattern is located in the pixel opening and is in contact with and connected to the conductive isolation structure.

[0028] In some embodiments, the step of making an isolation layer on the prefabricated board includes: depositing an isolation layer material on the pixel definition layer between the conductive isolation structure and the first electrode by evaporation to form the isolation layer.

[0029] In some embodiments, the step of making a light-emitting layer on a prefabricated board includes:

[0030] Depositing an organic light-emitting diode material on the first electrode by evaporation to form a first light-emitting unit; adjusting the evaporation angle so that the first light-emitting unit covers a portion of the isolation layer along the direction from the first electrode to the conductive isolation structure, so that a side of the isolation layer close to the conductive isolation structure is exposed;

[0031] By evaporating an N-type doped semiconductor material, a metal material and a P-type doped semiconductor material in sequence, an N-type doped layer, a metal spacer layer and a P-type doped layer stacked in sequence are deposited on the first light-emitting unit to form a connecting layer; wherein the exposed part of the isolation layer and the metal material repel each other, so that the metal spacer layer is spaced apart from the conductive isolation structure;

[0032] Repeat the steps of making the first light-emitting unit to form a second light-emitting unit on the connecting layer; adjust the evaporation angle so that the second light-emitting unit at least covers the connecting layer, so that the metal spacer layer and the second electrode are spaced apart from each other.

[0033] In some embodiments, the step of providing a prefabricated panel comprises:

[0034] Providing a drive substrate;

[0035] Manufacturing a metal layer on the driving substrate and patterning the metal layer to form a plurality of first electrodes;

[0036] A pixel definition layer is fabricated on the driving substrate; the pixel definition layer has a plurality of pixel openings, the pixel openings correspond to the first electrodes one by one, and the first electrodes are exposed to the pixel openings;

[0037] A conductive structure is fabricated on the pixel definition layer; the main body protrudes from the pixel definition layer and surrounds a pixel opening; the conductive structure is used to conduct the adjacent second electrode;

[0038] A top structure is fabricated on the conductive structure; the top structure shields the conductive structure and extends out of the conductive structure in a direction parallel to the pixel definition layer.

[0039] In order to solve the above technical problem, the third technical solution provided by the present application is: to provide a display device. The display device includes a circuit board and a display panel as mentioned in the above technical solution, and the circuit board is electrically connected to the display panel.

[0040] Beneficial effects of the present application: Different from the prior art, the present application provides a display panel and a method for manufacturing the same, and a display device. The display panel includes a drive substrate, a pixel definition layer, a conductive isolation structure, and a sub-pixel unit. Among them, by making the light-emitting layer include at least two stacked light-emitting units, and providing a connecting layer between each two adjacent light-emitting units, so that the sub-pixel unit becomes a light-emitting device composed of at least two stacked and series-connected light-emitting units, the display brightness and life of the display panel can be significantly improved. Furthermore, by arranging an isolation layer on the pixel definition layer within the pixel opening, the isolation layer extends along the pixel definition layer toward the conductive isolation structure and exceeds the edge of the light-emitting unit between the first electrode and the metal isolation layer to be exposed. At the same time, the isolation layer and the metal material repel each other, so that when preparing the metal isolation layer, it is impossible to form a film on the isolation layer, that is, to form an isolation belt, so as to prevent the metal isolation layer from extending to the conductive isolation structure and contacting the conductive isolation structure, resulting in the metal isolation layer being connected in series with the second electrode through the conductive structure. Even when the metal material is deposited on the conductive isolation structure due to diffusion when the metal isolation layer is manufactured, the metal material cannot adhere to the isolation layer, so that the metal isolation layer is disconnected at the isolation layer, so that the metal isolation layer located on the light-emitting unit cannot contact the conductive isolation structure and is connected in series with the second electrode, thereby effectively preventing the metal isolation layer from being connected in series with the conductive isolation structure, thereby improving the product yield of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. 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 any creative work.

[0042] Figure 1 is a schematic cross-sectional structure diagram of a display panel provided in the first embodiment of the present application;

[0043] Figure 2 is a schematic diagram of a stacked structure of a sub-pixel unit provided in an embodiment of the present application;

[0044] Figure 3 is a schematic cross-sectional structural diagram of a display panel provided in a second embodiment of the present application;

[0045] Figure 4 is a schematic cross-sectional structure diagram of a display panel provided in a third embodiment of the present application;

[0046] Figure 5 A schematic cross-sectional structure diagram of a display panel provided in a fourth embodiment of the present application;

[0047] Figure 6A schematic cross-sectional structure diagram of a display panel provided in a fifth embodiment of the present application;

[0048] Figure 7 is a schematic flow chart of a method for preparing a display panel provided in one embodiment of the present application;

[0049] Figure 8 is a schematic diagram of a process for preparing a display panel provided in one embodiment of the present application;

[0050] Fig. 9 It is a schematic flow chart of a method for preparing a light-emitting layer provided in one embodiment of the present application;

[0051] Fig.10 It is a schematic diagram of a process for preparing a light-emitting layer provided in one embodiment of the present application;

[0052] Fig.11 It is a schematic diagram of the structure of a display device provided in one embodiment of the present application.

[0053] Reference numerals:

[0054] 100-display panel; 10-driving substrate; 20-pixel definition layer; 30-conductive isolation structure; 31-conductive structure; 311-main structure; 312-metal oxide layer; 32-top structure; 40-sub-pixel unit; 41-first electrode; 42-light-emitting layer; 420-light-emitting unit; 421-first light-emitting unit; 422-second light-emitting unit; 43-connecting layer; 431-N-type doping layer; 432-metal spacer layer; 433-P-type doping layer; 44-second electrode; 50-isolation layer; 51-gap; 52-isolation belt;

[0055] HIL1-first hole injection layer; HTL1-first hole transport layer; EBL1-first electron blocking layer; EML1-first light-emitting layer; HBL1-first hole blocking layer; HTL2-second hole transport layer; EBL2-second electron blocking layer; EML2-second light-emitting layer; HBL2-second hole blocking layer; ETL2-second electron transport layer; EIL2-second electron injection layer. DETAILED DESCRIPTION

[0056] The scheme of the embodiment of the present application is described in detail below in conjunction with the drawings of the specification.

[0057] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures, interfaces, and technologies are provided to facilitate a thorough understanding of the present application.

[0058] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0059] The terms "first", "second", "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the embodiments of this application, all directional indications (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0060] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] The present application is described in detail below with reference to the accompanying drawings and embodiments.

[0062] See also Figure 1 , Figure 1 1 is a schematic cross-sectional view of a display panel provided in accordance with the first embodiment of the present application. In this embodiment, a display panel 100 is provided. The display panel 100 includes a driving substrate 10 , a pixel definition layer 20 and a sub-pixel unit 40 .

[0063] The driving substrate 10 includes a driving circuit for driving the sub-pixel unit 40 to emit light. The pixel definition layer 20 is disposed on the driving substrate 10 and has a plurality of pixel openings arranged in an array. The conductive isolation structure 30 is disposed protruding from the pixel definition layer 20 and surrounds the pixel opening. The sub-pixel unit 40 includes a first electrode 41, a light-emitting layer 42, and a second electrode 44 stacked in the pixel opening, and the second electrode 44 is contacted and connected with the conductive isolation structure 30. The light-emitting layer 42 includes at least two stacked light-emitting units 420, and a connecting layer 43 is provided between each two adjacent light-emitting units 420, and the connecting layer 43 includes a metal spacer layer 432. An isolation layer 50 is also provided in the pixel opening, and the isolation layer 50 is disposed on the pixel definition layer 20, and extends along the pixel definition layer 20 toward the conductive isolation structure 30 and is exposed beyond the edge of the light-emitting unit 420 located between the first electrode 41 and the metal spacer layer 432, and the isolation layer 50 and the metal material repel each other so that the metal spacer layer 432 and the conductive isolation structure 30 are spaced from each other.

[0064] In the embodiment of the present application, by making the light-emitting layer 42 include at least two stacked light-emitting units 420, and a connecting layer 43 is provided between every two adjacent light-emitting units 420, the sub-pixel unit 40 becomes a light-emitting device composed of at least two stacked and series-connected light-emitting units 420, which can significantly improve the display brightness and lifespan of the display panel 100.

[0065] Furthermore, by setting an isolation layer 50 on the pixel definition layer 20 in the pixel opening, the isolation layer 50 extends along the pixel definition layer 20 toward the conductive isolation structure 30 and exceeds the edge of the light-emitting unit 420 located between the first electrode 41 and the metal spacer layer 432 to be exposed. At the same time, the isolation layer 50 and the metal material repel each other, so that when preparing the metal spacer layer 432, a film cannot be formed on the isolation layer 50, that is, the exposed part of the isolation layer 50 forms an isolation belt 52 to prevent the metal spacer layer 432 from extending to the conductive isolation structure 30 and contacting the conductive isolation structure 30, resulting in the metal spacer layer 432 being connected in series with the second electrode 44 through the conductive structure 31. Furthermore, even if the metal material is diffused and deposited on the conductive isolation structure 30 when manufacturing the metal spacer layer 432, since the metal material cannot adhere to the isolation layer 50, the metal spacer layer 432 is disconnected at the isolation layer 50, so that the metal spacer layer 432 located on the light-emitting unit 420 cannot contact the conductive isolation structure 30 and is connected in series with the second electrode 44, thereby effectively blocking the metal spacer layer 432 from being connected in series with the conductive isolation structure 30, thereby improving the product yield of the display panel 100.

[0066] Specifically, the driving substrate 10 includes a driving circuit, which is electrically connected to the first electrode 41 and is used to drive the sub-pixel unit 40 to emit light; the driving substrate 10 can be a hard substrate or a flexible substrate, which can be specifically configured according to the usage scenario and usage requirements.

[0067] The pixel definition layer 20 protrudes from the driving substrate 10 to form a pixel opening for accommodating the sub-pixel unit 40. The pixel openings are arranged in an array, and can be arranged specifically according to the arrangement design of the sub-pixel unit 40. The pixel definition layer 20 can be patterned by a photolithography process, or can also be prepared by other patterning processes.

[0068] The sub-pixel unit 40 includes a first electrode 41, a light-emitting layer 42, and a second electrode 44 stacked in the pixel opening. Among them, the light-emitting layer 42 includes at least two stacked light-emitting units 420, and a connecting layer 43 is provided between each two adjacent light-emitting units 420, so that each light-emitting unit 420 is isomorphically connected in series through the connecting layer 43, thereby forming a series-type light-emitting device. In this embodiment, the sub-pixel unit 40 is a series-type OLED light-emitting device, and the sub-pixel unit 40 includes a plurality of OLED light-emitting units 420 connected in series through the connecting layer 43. The display panel 100 includes a plurality of sub-pixel units 40, and the sub-pixel unit 40 may specifically include three sub-pixels corresponding to the three primary colors to achieve full-color display, or may only include sub-pixels of one color, such as a blue sub-pixel, and then convert the color of the light through a quantum dot conversion layer to achieve full-color display, or may only include sub-pixels of one color when used as a light source, and the sub-pixel color may be specifically set according to actual needs. On the display panel 100, a plurality of sub-pixel units 40 may be arranged according to a preset rule to achieve the desired display effect.

[0069] Specifically, the sub-pixel unit 40 includes a first electrode 41, a first light-emitting unit 421, a connecting layer 43, a second light-emitting unit 422, and a second electrode 44 stacked in sequence. Of course, in other embodiments, the sub-pixel unit 40 may also include more light-emitting units 420 and connecting layers 43, which may be specifically arranged as needed.

[0070] Among them, the conductive isolation structure 30 is used to isolate each sub-pixel unit 40. Specifically, the conductive isolation structure 30 separates the light-emitting layers 42 of each sub-pixel unit 40, and separates the second electrodes 44 of sub-pixels of different colors, to avoid pixel crosstalk. At the same time, the second electrode 44 of each sub-pixel unit 40 is arranged in contact with the conductive isolation structure 30 and is connected, so that the second electrodes 44 of each sub-pixel unit 40 are connected through the conductive isolation structure 30, so as to achieve a mesh connection between different sub-pixel units 40 and realize the uniformity of the entire surface signal of the second electrode 44.

[0071] Specifically, the conductive isolation structure 30 includes a conductive structure 31 and a top structure 32 which are stacked in sequence. The conductive structure 31 is protrudingly arranged on the pixel definition layer 20 and surrounds the pixel opening; the top structure 32 is located on the upper surface of the conductive structure 31 to shield the conductive structure 31 and extend the conductive structure 31 in a direction parallel to the pixel definition layer 20. That is, the top structure 32 is arranged in contact with the conductive structure 31, and the orthographic projection of the top structure 32 on the driving substrate 10 completely covers the orthographic projection of the conductive structure 31 on the driving substrate 10. Specifically, the portion of the top structure 32 extending out of the conductive structure 31 is suspended relative to the conductive structure 31. When evaporating the light-emitting layer 42 and the second electrode 44, the evaporation angle can be adjusted by the suspended portion of the top structure 32 to adjust the edge range size of each film layer in the light-emitting layer 42. There are multiple conductive isolation structures 30, and two adjacent conductive isolation structures 30 share the same side of the conductive isolation structure 30 to ensure that the spacing between each sub-pixel unit 40 is equal, which is conducive to display uniformity. Specifically, the conductive isolation structure 30 is a ring-shaped structure, which specifically matches the shape of the sub-pixel unit 40, so as to be used to prepare the sub-pixel unit 40 to form a preset shape.

[0072] In a direction perpendicular to the driving substrate 10 , the longitudinal section of the side wall of the conductive structure 31 is trapezoidal, and the cross section of the side wall of the conductive structure 31 gradually decreases in a direction close to the top structure 32 to facilitate the contact setting of the second electrode 44 with the conductive structure 31 .

[0073] In the present embodiment, the first electrode 41 includes a metal material, such as silver (Ag), gold (Au) and other metal materials. The isolation layer 50 includes a cathode patterning material (CPM). In some embodiments, the CPM material is a fluorine-containing organic material, such as a substituted fluorinated cyclotriphosphinate compound. The CPM material can be deposited on the drive substrate 10 by low-temperature vacuum evaporation to form the above-mentioned isolation layer 50. In other embodiments, the CPM material may not be a fluorine-containing organic material, as long as the CPM material and the metal material are incompatible and mutually repel each other. When making the isolation layer 50, the CPM material can be evaporated through the top structure 32. At the same time, since the first electrode 41 includes a metal material, the CPM material cannot be attached to the surface of the first electrode 41 during the evaporation process. Therefore, the CPM material can only be deposited on the pixel definition layer 20 exposed in the pixel opening to form the isolation layer 50, so that the preparation of the isolation layer 50 can be completed without using a mask. Specifically, the isolation layer 50 surrounds the first electrode 41 to form a ring structure. Along the radial direction of the ring structure, the width of the isolation layer 50 can be adjusted by the evaporation angle, that is, the size of the outer edge range of the isolation layer 50 can be adjusted by adjusting the evaporation angle. Since the outer position of the first electrode 41 is fixed, the isolation layer 50 extends from the side of the pixel definition layer 20 close to the first electrode 41 to the direction close to the conductive structure 31, and the extension length is determined by the evaporation angle. In the embodiment of the present application, the isolation layer 50 extends along the pixel definition layer 20 to the conductive structure 31 and has a preset gap 51 with the conductive structure 31, or extends to the conductive structure 31 and contacts the conductive structure 31.

[0074] In this embodiment, the conductive structure 31 may include a metal material, and the isolation layer 50 extends along the pixel definition layer 20 toward the conductive isolation structure 30, and has a preset gap 51 with the conductive structure 31. It can be understood that, since the material of the isolation layer 50 and the metal material repel each other, the preset gap 51 may be naturally formed in the process of manufacturing the isolation layer 50, or the size of the preset gap 51 may be adjusted by adjusting the evaporation angle.

[0075] The first light-emitting unit 421 is disposed on the first electrode 41, extending outward with the first electrode 41 as the center, covering a portion of the isolation layer 50 close to the first electrode 41, and exposing a portion of the isolation layer 50 close to the conductive structure 31; that is, the isolation layer 50 extends along the pixel definition layer 20 toward the conductive isolation structure 30 and exceeds the edges of the first light-emitting unit 421 and the N-type doped layer 431 to be exposed, and the exposed portion of the isolation layer 50 forms an annular isolation zone 52.

[0076] The connecting layer 43 includes an N-type doped layer 431, a metal spacer layer 432 and a P-type doped layer 433 which are stacked in sequence; wherein the N-type doped layer 431 covers the first light emitting unit 421 and exposes a portion of the isolation layer 50 close to the conductive structure 31; that is, the N-type doped layer 431 is located within the range enclosed by the annular isolation belt 52 so that the annular isolation belt 52 is exposed, and the metal spacer layer 432 is disposed on the N-type doped layer 431. Since the annular isolation belt 52 repels the metal material, when the metal spacer layer 432 is prepared, the metal spacer layer 432 can be prevented from extending to the conductive structure 31 and contacting the conductive spacer structure, causing the metal spacer layer 432 to 2 is connected in series with the second electrode 44 through the conductive structure 31; moreover, even when the metal spacer layer 432 is manufactured, the metal material is deposited on the conductive structure 31 due to diffusion, and the metal material cannot be attached to the exposed isolation belt 52, so that the metal spacer layer 432 is disconnected at the isolation belt 52, so that the metal spacer layer 432 located on the light-emitting unit 420 cannot contact with the conductive structure 31, and therefore cannot be connected in series with the second electrode 44, thereby effectively preventing the metal spacer layer 432 from contacting with the conductive structure 31, effectively reducing the risk of the metal spacer layer 432 being connected in series with the second electrode 44 through the conductive structure 31, and improving the product yield of the display panel 100.

[0077] Furthermore, the second light-emitting unit 422 at least covers the connection layer 43, so that the metal spacer layer 432 and the second electrode 44 are spaced apart from each other. That is, by making the second light-emitting unit 422 cover the connection layer 43 to cover the metal spacer layer 432 therein, so that the metal spacer layer 432 is spaced apart from the second electrode 44 through the second light-emitting unit 422, the problem of the metal spacer layer 432 being exposed and contacting with the second electrode 44 to form a series connection can be avoided, and the product yield rate is further improved.

[0078] Please refer to Figure 2 , Figure 2 Schematic diagram of the stacked structure of a sub-pixel unit 40 provided in an embodiment of the present application. Specifically, in this embodiment, the sub-pixel light-emitting unit 420 includes a first electrode 41, a first light-emitting unit 421, a connecting layer 43, a second light-emitting unit 422 and a second electrode 44 stacked in sequence.

[0079] The first light-emitting unit 421 includes a first hole injection layer HIL1, a first hole transport layer HTL1, a first electron blocking layer EBL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, and a first electron transport layer stacked in sequence on the first electrode 41. The connecting layer 43 includes an N-type doped layer 431, a metal spacer layer 432, and a P-type doped layer 433 stacked in sequence on the first light-emitting unit 421. The second light-emitting unit 422 includes a second hole transport layer HTL2, a second electron blocking layer, a second light-emitting layer EML2, a second hole blocking layer HBL2, a second electron transport layer ETL2, and a second electron injection layer EIL2 stacked in sequence on the connecting layer 43.

[0080] After the driving substrate 10 transmits a driving signal to the sub-pixel unit 40, under the drive of the external electric field, the first electrode 41 can generate positively charged holes, the second electrode 44 can generate negatively charged electrons, and the contact area of ​​the N-type doped layer 431 and the P-type doped layer 433 in the connecting layer 43 generates holes and electrons. At this time, the holes generated by the first electrode 41 can enter the first light-emitting layer EML1 through the first hole injection layer HIL1, the first hole transport layer HTL1 and the first electron blocking layer EBL1 in sequence; accordingly, the electrons generated by the contact area of ​​the N-type doped layer 431 and the P-type doped layer 433 can enter the first light-emitting layer EML1 through the N-type doped layer 431, the first electron transport layer and the first hole blocking layer HBL1 in sequence. Similarly, the electrons and holes enter the second light-emitting layer EML2 in the same way. At this time, the holes and electrons in the first light-emitting layer EML1 and the holes and electrons in the second light-emitting layer EML2 are combined to form excitons, so that the sub-pixel unit 40 emits light.

[0081] In this embodiment, the isolation layer 50 extends along the pixel definition layer 20 and has a gap 51 with the conductive isolation structure 30; the second electrode 44 covers the second light-emitting unit 422 and extends to the gap 51 to be in contact and electrically connected with the conductive isolation structure 30. It can be understood that the isolation layer 50 has a gap 51 between the side close to the conductive isolation structure 30 and the conductive structure 31, and does not contact the conductive structure 31. The second electrode 44 extends to the gap 51 to fill the gap 51, so that the contact area between the second electrode 44 and the conductive structure 31 is increased, thereby improving the conductivity effectiveness.

[0082] In this embodiment, the side of the second light-emitting unit 422 close to the conductive isolation structure 30 overlaps with the side of the isolation layer 50 close to the conductive structure 31 in a direction perpendicular to the driving substrate 10, or the side of the second light-emitting unit 422 close to the conductive structure 31 is located in the area enclosed by the side of the isolation layer 50 close to the conductive structure 31, so that the second light-emitting unit 422 and the isolation layer 50 form a step structure on the side close to the conductive structure 31, which is beneficial to the deposition of the second electrode 44.

[0083] See also Figure 3 , Figure 3 1 is a schematic diagram of the cross-sectional structure of the display panel 100 provided in the second embodiment of the present application. Different from the first embodiment, in this embodiment, the second light-emitting unit 422 covers the connection layer 43 and the isolation layer 50, and extends into the gap 51 between the isolation layer 50 and the conductive isolation structure 30, so that the second light-emitting unit 422 and the conductive isolation structure 30 are relatively flat, which is conducive to the deposition of the second electrode 44, avoiding uneven film thickness of the second electrode 44 due to uneven terrain, and reducing the risk of disconnection of the second electrode 44.

[0084] In this embodiment, the conductive structure 31 may include a metal material, and since the isolation layer 50 and the metal material repel each other, a certain gap may be naturally formed between the isolation layer 50 and the conductive structure 31. Alternatively, the size of the preset gap 51 may be adjusted by adjusting the evaporation angle.

[0085] See also Figure 4 , Figure 4 3 is a schematic diagram of the cross-sectional structure of a display panel provided in the third embodiment of the present application. Different from the first and second embodiments, in this embodiment, the isolation layer 50 extends along the pixel definition layer 20 and contacts the conductive isolation structure 30, and the second electrode 44 covers the second light-emitting unit 422 and the isolation layer 50, and is electrically connected to the conductive isolation structure 30.

[0086] In this embodiment, the conductive structure 31 may include a main structure 311 and a metal oxide layer 312 disposed on the surface of the main structure 311. The main structure 311 includes a metal material, so that the isolation layer 50 can extend to the conductive structure 31 and contact the conductive structure 31. By making the isolation layer 50 contact the conductive structure 31, the terrain of the location area is flat, which is conducive to the deposition of the second electrode 44 and the contact setting with the conductive structure 31.

[0087] In the embodiment of the present application, the isolation layer 50 is spaced apart from the side of the first electrode 41 that is close to each other, thereby ensuring that the contact area between the first light-emitting unit 421 and the first electrode 41 is not affected, thereby avoiding a reduction in the light-emitting area of ​​the first light-emitting unit 421 .

[0088] See also Figure 5 , Figure 5The cross-sectional structure diagram of the display panel provided in the fourth embodiment of the present application. In this embodiment, the isolation layer 50 covers part of the side wall surface 22 of the pixel definition layer 20 and the upper surface 21 of the pixel definition layer 20, and extends along the upper surface 21 to the conductive isolation structure 30. The pixel definition layer 20 has a side wall surface 22 and an upper surface 21, the side surface of the pixel definition layer 20 surrounding the pixel opening is the side wall surface 22, and the surface of the pixel definition layer 20 away from the driving substrate 10 is the upper surface 21.

[0089] In this embodiment, the isolation layer 50 covers part of the side wall surface 22 of the pixel definition layer 20, and is spaced apart from the first electrode 41, so that the first light-emitting unit 421 can fully cover the part of the first electrode 41 exposed by the pixel definition layer 20, thereby avoiding the problem of reducing the light-emitting area of ​​the first light-emitting unit 421. Specifically, the isolation layer 50 can cover part of the side wall surface 22 by adjusting the evaporation angle of the CPM material.

[0090] See also Figure 6 , Figure 6 A schematic diagram of the cross-sectional structure of a display panel provided in the fifth embodiment of the present application. In this embodiment, the isolation layer 50 only covers the upper surface 21 of the pixel definition layer 20, and extends along the upper surface 21 to the conductive isolation structure 30. That is, the CPM material is only deposited on the upper surface 21 of the pixel definition layer 20, and extends to the conductive structure 31 of the conductive isolation structure 30, and is partially attached to the conductive structure 31, which can not only further improve the isolation effect of the isolation layer 50, but also will not block the angle of the first light-emitting unit 421, and will not affect the deposition area of ​​the first light-emitting unit 421, thereby avoiding the reduction of the light-emitting area of ​​the first light-emitting unit 421.

[0091] Specifically, the display panel 100 provided in the above embodiment can be prepared by the preparation method described below, and the details can be referred to the detailed description below.

[0092] See also Figure 7 and Figure 8 , Figure 7 is a schematic diagram of a method for preparing a display panel provided in one embodiment of the present application, Figure 8 1 is a schematic diagram of a process for preparing a display panel according to an embodiment of the present application. In this embodiment, a method for preparing a display panel 100 is provided, and the method is used to prepare the display panel 100 involved in the above embodiments.

[0093] Specifically, the preparation method comprises:

[0094] S1: Provide a prefabricated board. The prefabricated board includes a driving substrate 10, a first electrode 41, a pixel definition layer 20 and a conductive isolation structure 30; wherein the first electrode 41 and the pixel definition layer 20 are arranged on the driving substrate 10, the pixel definition layer 20 has a plurality of pixel openings, and the first electrode 41 is located in the pixel openings; the conductive isolation structure 30 protrudes from the pixel definition layer 20 and surrounds the pixel openings.

[0095] S2: Making an isolation layer 50 on the prefabricated board. The isolation layer 50 is located on the pixel definition layer 20 in the pixel opening and extends along the pixel definition layer 20 toward the conductive isolation structure 30. The isolation layer 50 and the metal material repel each other.

[0096] S3: Making a light-emitting layer 42 on the prefabricated board. The light-emitting layer 42 includes at least two light-emitting units 420 stacked in the pixel opening, and a connection layer 43 is provided between every two adjacent light-emitting units 420, and the connection layer 43 includes a metal spacer layer 432; wherein the light-emitting units 420 between the first electrode 41 and the metal spacer layer 432 are located in the area surrounded by the outer edge of the isolation layer 50, so as to expose the side of the isolation layer 50 close to the conductive isolation structure 30, so that the metal spacer layer 432 is spaced apart from the conductive isolation structure 30.

[0097] S4: manufacturing a second electrode 44 on the light emitting layer 42. The second electrode 44 is located in the pixel opening and is in contact with and conductive to the conductive isolation structure 30.

[0098] In this embodiment, after step S2, in step S3, the metal isolation layer 50 cannot be formed on the exposed portion of the isolation layer to prevent the metal isolation layer 432 from contacting the conductive isolation layer 50, which can significantly reduce the risk of the metal isolation layer 432 being connected in series with the second electrode 44 through the conductive isolation layer 50. Specifically, the structure and function of the isolation layer 50 are the same or similar to those of the isolation layer 50 involved in the above embodiment, and the details can be referred to the above description, which will not be repeated here.

[0099] Wherein, step S1 specifically includes:

[0100] S11: providing a driving substrate 10 .

[0101] S12 : manufacturing a metal layer on the driving substrate 10 , and patterning the metal layer to form a plurality of first electrodes 41 .

[0102] S13: manufacturing the pixel definition layer 20 on the driving substrate 10. The pixel definition layer 20 has a plurality of pixel openings, the pixel openings correspond to the first electrodes 41 one by one, and the first electrodes 41 are exposed to the pixel openings.

[0103] S14: manufacturing a conductive structure 31 on the pixel definition layer 20. The main body protrudes from the pixel definition layer 20 and surrounds the pixel opening; the main body is used to conduct the adjacent second electrode 44.

[0104] S15: manufacturing a top structure 32 on the main body portion. The top structure 32 covers the main body structure 311 and extends out of the main body structure 311 in a direction parallel to the pixel definition layer 20 .

[0105] Among them, the specific structure and function of the driving substrate 10, the pixel definition layer 20, the first electrode 41, and the conductive isolation structure 30 are the same or similar to the specific structure and function of the driving substrate 10, the pixel definition layer 20, the first electrode 41, and the conductive isolation structure 30 involved in the above embodiments, and please refer to the above introduction for details.

[0106] Specifically, the first electrode 41 includes a metal material.

[0107] The step S2 may specifically include: depositing a CPM material on the pixel definition layer 20 between the conductive isolation structure 30 and the first electrode 41 by evaporation to form the isolation layer 50. The isolation layer 50 includes a CPM material.

[0108] In this step, since the top structure 32 of the conductive isolation structure 30 has a suspended portion, the CPM material can be directly deposited on the pixel definition layer 20 by evaporation without using a mask, and since the first electrode 41 is a metal material, the CPM material cannot adhere to the surface of the first electrode 41. Therefore, the CPM material can only be deposited on the pixel definition layer 20 between the conductive isolation structure 30 and the first electrode 41, without affecting the first electrode 41.

[0109] Furthermore, the width of the isolation layer 50 of the annular structure in the radial direction can be adjusted by adjusting the evaporation angle, so that the isolation layer 50 and the conductive isolation structure 30 are spaced apart or in contact with each other.

[0110] Please refer to Fig. 9 and Fig.10 , Fig. 9 is a schematic flow chart of a method for preparing a light-emitting layer provided in one embodiment of the present application, Fig.10 It is a schematic diagram of the process for preparing the light-emitting layer provided in one embodiment of the present application.

[0111] In this implementation, step S3 specifically includes:

[0112] S31: Depositing an organic light-emitting diode material on the first electrode 41 by evaporation to form a first light-emitting unit 421. By adjusting the evaporation angle, the first light-emitting unit 421 covers a portion of the isolation layer 50 along the direction from the first electrode 41 to the conductive isolation structure 30, so that a side of the isolation layer 50 close to the conductive isolation structure 30 is exposed.

[0113] S32: By evaporation, N-type doped semiconductor material, metal material and P-type doped semiconductor material are sequentially deposited on the first light-emitting unit 421 to form a stacked N-type doped layer 431, a metal spacer layer 432 and a P-type doped layer 433, so as to form a connecting layer 43. The exposed part of the isolation layer 50 and the metal material repel each other, so that the metal spacer layer 432 is spaced apart from the conductive isolation structure 30.

[0114] S33: Repeat the steps of making the first light-emitting unit 421 to form a second light-emitting unit 422 on the connection layer 43. By adjusting the evaporation angle, the second light-emitting unit 422 at least covers the connection layer 43, so that the metal spacer layer 432 and the second electrode 44 are spaced apart from each other.

[0115] In this embodiment, each film layer in the light-emitting layer 42 can be produced by evaporation through the conductive isolation structure 30, that is, the conductive isolation structure 30 is used instead of the mask to produce each film layer. Specifically, before evaporating each film layer, the evaporation angle is adjusted to adjust the deposition area range of each film layer. Specifically, by adjusting the evaporation angle, the first light-emitting unit 421 covers part of the isolation layer 50 along the direction from the first electrode 41 to the conductive isolation structure 30, so that the side of the isolation layer 50 close to the conductive isolation structure 30 is exposed to form an annular isolation belt 52, so that when the connecting layer 43 is produced, the metal spacer layer 432 cannot contact the conductive isolation structure 30. By adjusting the evaporation angle, the second light-emitting unit 422 at least covers the connecting layer 43, so that the metal spacer layer 432 and the second electrode 44 are spaced from each other to avoid contact between the second electrode 44 and the metal spacer layer 432.

[0116] In this embodiment, the first electrode 41 is an anode and the second electrode 44 is a cathode. In other embodiments, the first electrode 41 may also be a cathode and the second electrode 44 may be an anode. The first electrode 41 and the second electrode 44 may be specifically set as an anode and a cathode according to the actual drive circuit design, and there is no limitation on this.

[0117] See also Fig.11 , Fig.11 1 is a schematic diagram of the structure of a display device provided in an embodiment of the present application. In this embodiment, a display device is provided, which can be used in the fields of tablets, mobile phones, vehicles, lighting, etc.

[0118] The display device includes a display panel 100 and a circuit board (not shown), the circuit board is electrically connected to the display panel 100, and is used to provide the display panel 100 with various drive signals, power signals and other drive signals required by the display panel 100. Among them, the specific structure and function of the display panel 100 are the same or similar to the specific structure and function of the display panel 100 in the above embodiment, and the same technical effect can be achieved. For details, please refer to the above introduction. Specifically, the display panel 100 can be prepared by the preparation method provided in the above embodiment. The display device can effectively improve the display brightness and pixel density, and can improve the product yield.

[0119] The above are only implementation methods of the present application, and are not intended to limit the patent protection scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A display panel, comprising: Driver substrate; A pixel definition layer, disposed on the driving substrate and having a plurality of pixel openings; A conductive isolation structure protrudes from the pixel definition layer and surrounds the pixel opening; The sub-pixel unit comprises a first electrode, a light-emitting layer and a second electrode stacked in the pixel opening; the second electrode is in contact with and conductive to the conductive isolation structure; The invention is characterized in that the light-emitting layer comprises at least two stacked light-emitting units, and a connecting layer is provided between every two adjacent light-emitting units; the connecting layer comprises a metal spacer layer; An isolation layer is also provided in the pixel opening. The isolation layer is arranged on the pixel definition layer and extends along the pixel definition layer toward the conductive isolation structure and beyond the edge of the light-emitting unit between the first electrode and the metal isolation layer to be exposed. The isolation layer and the metal material repel each other so that the metal isolation layer and the conductive isolation structure are spaced apart from each other.

2. The display panel according to claim 1, characterized in that: The first electrode includes a metal material, and the isolation layer includes a cathode patterning material.

3. The display panel according to claim 1, characterized in that: The light-emitting layer includes a first light-emitting unit and a second light-emitting unit which are stacked, and the first light-emitting unit is arranged between the first electrode and the connecting layer; The connection layer includes an N-type doping layer, the metal spacer layer and a P-type doping layer stacked in sequence; The isolation layer extends along the pixel definition layer toward the conductive isolation structure and is exposed beyond the edges of the first light emitting unit and the N-type doping layer, so that the metal isolation layer and the conductive isolation structure are spaced apart from each other; The second light emitting unit at least covers the connection layer, so that the metal spacer layer and the second electrode are spaced apart from each other.

4. The display panel according to claim 3, characterized in that: The isolation layer extends along the pixel definition layer and has a gap with the conductive isolation structure; the second electrode covers the second light-emitting unit and extends to the gap to be in contact with and electrically connected to the conductive isolation structure; or, The isolation layer extends along the pixel definition layer and contacts the conductive isolation structure. The second electrode covers the second light emitting unit and the isolation layer and is electrically connected to the conductive isolation structure.

5. The display panel according to claim 1, characterized in that: The isolation layer is spaced apart from a side of the first electrode that is close to each other; Wherein, the isolation layer covers part of the side wall surface of the pixel definition layer and the upper surface of the pixel definition layer, and extends along the upper surface to the conductive isolation structure; or, The isolation layer only covers the upper surface of the pixel definition layer and extends along the upper surface to the conductive isolation structure.

6. A method for preparing a display panel, characterized in that: include: Provide prefabricated panels; The prefabricated board includes a driving substrate, a first electrode, a pixel definition layer and a conductive isolation structure; wherein the first electrode and the pixel definition layer are arranged on the driving substrate, the pixel definition layer has a plurality of pixel openings, and the first electrode is located in the pixel openings; the conductive isolation structure protrudes from the pixel definition layer and surrounds the pixel openings; An isolation layer is fabricated on the prefabricated plate; the isolation layer is located on the pixel definition layer in the pixel opening and extends along the pixel definition layer toward the conductive isolation structure, and the isolation layer and the metal material repel each other; A light-emitting layer is fabricated on the prefabricated board; the light-emitting layer comprises at least two light-emitting units stacked in the pixel opening, and a connection layer is provided between every two adjacent light-emitting units, and the connection layer comprises a metal spacer layer; wherein the light-emitting unit between the first electrode and the metal spacer layer is located in the area surrounded by the outer edge of the isolation layer, so that the side of the isolation layer close to the conductive isolation structure is exposed, so that the metal spacer layer and the conductive isolation structure are spaced apart; A second electrode is manufactured on the light-emitting layer; the second electrode pattern is located in the pixel opening and is in contact with and connected to the conductive isolation structure.

7. The preparation method according to claim 6, characterized in that: The step of making the isolation layer on the prefabricated board includes: depositing the isolation layer material on the pixel definition layer between the conductive isolation structure and the first electrode by evaporation to form the isolation layer.

8. The preparation method according to claim 6, characterized in that: The step of manufacturing the light-emitting layer on the prefabricated board comprises: Depositing an organic light-emitting diode material on the first electrode by evaporation to form a first light-emitting unit; adjusting the evaporation angle so that the first light-emitting unit covers a portion of the isolation layer along a direction from the first electrode to the conductive isolation structure, so that a side of the isolation layer close to the conductive isolation structure is exposed; By evaporating an N-type doped semiconductor material, a metal material and a P-type doped semiconductor material in sequence, a stacked N-type doped layer, the metal spacer layer and a P-type doped layer are sequentially deposited on the first light-emitting unit to form the connecting layer; wherein the exposed portion of the isolation layer and the metal material repel each other, so that the metal spacer layer and the conductive isolation structure are spaced apart; Repeat the steps of making the first light-emitting unit to form a second light-emitting unit on the connecting layer; adjust the evaporation angle so that the second light-emitting unit at least covers the connecting layer, so that the metal spacer layer and the second electrode are spaced apart from each other.

9. The preparation method according to claim 6, characterized in that: The step of providing the prefabricated panels comprises: Providing a drive substrate; Manufacturing a metal layer on the driving substrate, and patterning the metal layer to form a plurality of the first electrodes; The pixel definition layer is manufactured on the driving substrate; the pixel definition layer has a plurality of pixel openings, the pixel openings correspond to the first electrodes one by one, and the first electrodes are exposed to the pixel openings; A conductive structure is fabricated on the pixel definition layer; the conductive structure protrudes from the pixel definition layer and surrounds the pixel opening; the conductive structure is used to conduct the adjacent second electrode; A top structure is fabricated on the conductive structure; the top structure shields the conductive structure and extends out of the conductive structure in a direction parallel to the pixel definition layer.

10. A display device, characterized in that: The invention comprises a circuit board and a display panel as claimed in any one of claims 1 to 5, wherein the circuit board is electrically connected to the display panel.

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