阅读说明：本技术 一种阵列基板、其制备方法及显示装置 (Array substrate, preparation method thereof and display device ) 是由 梅文海 于 2020-04-29 设计创作，主要内容包括：本发明公开了一种阵列基板、其制备方法及显示装置,通过将像素界定层中与发光功能层接触的部分设置成具有在外部条件变化下在亲水性与疏水性之间转换的功能,这样在形成发光功能层的各膜层时,由于发光功能层的各膜层亲、疏水性不一致,如在形成亲水性的发光功能层时,将像素界定层在外部条件处理下使与发光功能层接触的部分转换呈疏水性,在形成疏水性的发光功能层时,将像素界定层在外部条件处理下使与发光功能层接触的部分转换呈亲水性,从而可以使开口区域内形成的发光功能层不会向像素界定层内壁攀爬,从而使开口区域内形成的发光功能层膜厚均一,提高显示面板的显示效果和发光器件的寿命。(The invention discloses an array substrate, a preparation method thereof and a display device, wherein a part of a pixel defining layer, which is in contact with a light-emitting functional layer, is set to have a function of switching between hydrophilicity and hydrophobicity under the change of external conditions, so that when each film layer of the light-emitting functional layer is formed, because the hydrophilicity and the hydrophobicity of each film layer of the luminous functional layer are not consistent, when the hydrophilic luminous functional layer is formed, the pixel defining layer is converted to be hydrophobic at a portion in contact with the light emitting function layer under an external condition treatment, when a hydrophobic light-emitting functional layer is formed, the pixel defining layer is converted into hydrophilic property at a portion in contact with the light-emitting functional layer under an external condition treatment, so that the light emitting function layer formed in the opening region does not climb to the inner wall of the pixel defining layer, therefore, the thickness of the luminous functional layer formed in the opening region is uniform, and the display effect of the display panel and the service life of the light-emitting device are improved.)

1. An array substrate, comprising a substrate, a pixel defining layer on one side of the substrate, wherein the pixel defining layer has a plurality of opening regions, the opening regions include a light-emitting functional layer therein, and a portion of the pixel defining layer in contact with the light-emitting functional layer has a function of switching between hydrophilic and hydrophobic properties under a change in external conditions.

2. The array substrate of claim 1, wherein the pixel defining layer comprises a first pixel defining layer, and a second pixel defining layer on a side of the first pixel defining layer away from the substrate base plate;

the first pixel defining layer comprises a plurality of pixel defining structures which surround each opening region and are independent of each other, and the pixel defining structures are in contact with the light emitting functional layer;

the second pixel defining layer covers the plurality of pixel defining structures, the structure of the second pixel defining layer is a grid-shaped structure exposing each opening region, and the second pixel defining layer is used for insulating adjacent pixel defining structures from each other.

3. The array substrate of claim 2, wherein a thickness of the pixel defining structure is greater than a thickness of the light emitting functional layer in a direction of the base substrate toward the pixel defining layer.

4. The array substrate of claim 2, wherein the first pixel defining layer is changed from hydrophilic to hydrophobic or from hydrophobic to hydrophilic under ultraviolet irradiation.

5. The array substrate of claim 4, wherein the first pixel defining layer is made of azobenzene, spiropyran, cinnamic acid, titanium dioxide, or vanadium pentoxide; the material of the second pixel defining layer is an insulating material.

6. The array substrate of claim 2, wherein the first pixel defining layer has a thickness of 100nm to 200nm and the second pixel defining layer has a thickness of 50nm to 150 nm.

7. The array substrate of claim 1, wherein the light-emitting functional layer comprises a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer, which are sequentially stacked.

8. The array substrate of claim 7, wherein the hole injection layer and the electron transport layer are hydrophilic and the hole transport layer and the light emitting layer are hydrophobic.

9. The array substrate of claim 7, wherein the material of the light emitting layer is a quantum dot material.

10. A display device comprising the array substrate according to any one of claims 1 to 9.

11. A preparation method of an array substrate is characterized by comprising the following steps:

forming a pixel defining layer having a plurality of opening regions on a substrate;

forming a light emitting function layer in each of the opening regions; wherein a portion of the pixel defining layer in contact with the light emitting function layer has a function of switching between hydrophilicity and hydrophobicity under a change in external conditions.

12. The method according to claim 11, wherein forming a pixel defining layer having a plurality of open regions on a substrate comprises:

spin-coating a first photoresist on the substrate base plate, and forming a patterned first photoresist layer after exposing and developing the first photoresist;

preparing a first pixel defining material layer on the substrate base plate with the first photoresist layer in a spin coating mode;

stripping the first photoresist layer to remove the first photoresist layer and the first pixel defining material layer above the first photoresist layer to form a plurality of pixel defining structures surrounding each opening region and independent of each other, each pixel defining structure constituting the first pixel defining layer;

depositing a film layer of insulating material on the first pixel defining layer at a side away from the substrate base plate;

patterning the insulating material film layer to expose each opening region so as to form a second pixel defining layer; the second pixel defining layer covers the plurality of pixel defining structures, the structure of the second pixel defining layer is a grid-shaped structure exposing each opening region, and the second pixel defining layer is used for insulating adjacent pixel defining structures from each other.

13. The method according to claim 12, wherein forming a luminescent functional layer in each of the open regions specifically comprises:

processing the substrate base plate on which the second pixel defining layer is formed under a first external condition to make the first pixel defining layer hydrophobic;

forming a hole injection layer in each opening region by adopting an ink-jet printing process;

processing the substrate base plate with the hole injection layer under a second external condition to make the first pixel defining layer hydrophilic;

forming a hole transport layer on one side of the hole injection layer, which is far away from the substrate base plate, by adopting an ink-jet printing process;

forming a light-emitting layer on one side of the hole transport layer, which is far away from the substrate base plate, by adopting an ink-jet printing process;

processing the substrate on which the light emitting layer is formed under the first external condition to make the first pixel defining layer hydrophobic;

and forming an electron transmission layer on one side of the light-emitting layer, which is far away from the substrate base plate, by adopting an ink-jet printing process.

Technical Field

The invention relates to the technical field of display, in particular to an array substrate, a preparation method thereof and a display device.

Background

An Organic Light Emitting Diode (OLED) display has the advantages of low power consumption, self-luminescence, wide viewing angle, and fast response speed, and is one of the hot spots in the research field of current displays, and is considered as the next generation display technology.

Currently, the methods for forming a light emitting layer in an OLED display mainly include an evaporation method and an inkjet printing method. The evaporation method is mature in application of film formation in the preparation of the small-size OLED display, and the ink-jet printing method is considered as an important method for realizing mass production of the large-size OLED display because the film formation speed is high and the material utilization rate is high, so that large-size film formation can be realized. Generally, when each film layer of the light-emitting functional layer is manufactured, a pixel defining layer is manufactured on a substrate to limit the area where each pixel is located, and then the light-emitting functional layer is manufactured in the corresponding pixel-specific opening area by adopting an ink-jet printing process.

However, when a plurality of layers of the light-emitting functional layer are printed, a thin film having a non-uniform thickness (having a thick both sides and a thin middle part) is easily formed due to the magnanite effect (a phenomenon in which a mass moves due to a gradient of tension between interfaces of two liquids having different surface tensions), and thus a thin film layer is easily formed in the middle of an opening region, and the thin film layer is broken down by a high voltage in a final device. Meanwhile, the non-uniformity of the film layer in the opening region tends to reduce the light emitting efficiency and lifetime of the device, so how to form a light emitting functional layer with uniform film thickness in the opening region is a crucial step in the OLED process.

Disclosure of Invention

In view of the above, embodiments of the present invention provide an array substrate, a method for manufacturing the same, and a display device, so as to solve the problem in the prior art that the display effect is not good due to non-uniform film thickness of a light emitting functional layer caused by the magnanite effect.

Therefore, an embodiment of the present invention provides an array substrate, including a substrate, and a pixel defining layer on one side of the substrate, where the pixel defining layer has a plurality of opening regions, the opening regions include a light-emitting functional layer therein, and a portion of the pixel defining layer in contact with the light-emitting functional layer has a function of switching between hydrophilicity and hydrophobicity under a change in an external condition.

Optionally, in practical implementation, in the array substrate provided in this embodiment of the present invention, the pixel defining layer includes a first pixel defining layer, and a second pixel defining layer located on a side of the first pixel defining layer away from the substrate;

the first pixel defining layer comprises a plurality of pixel defining structures which surround each opening region and are independent of each other, and the pixel defining structures are in contact with the light emitting functional layer;

the second pixel defining layer covers the plurality of pixel defining structures, the structure of the second pixel defining layer is a grid-shaped structure exposing each opening region, and the second pixel defining layer is used for insulating adjacent pixel defining structures from each other.

Optionally, in a specific implementation, in the array substrate provided in the embodiment of the present invention, a thickness of the pixel defining structure is greater than a thickness of the light emitting function layer along a direction in which the substrate points to the pixel defining layer.

Optionally, in a specific implementation manner, in the array substrate provided in an embodiment of the present invention, the first pixel defining layer is changed from a hydrophilic property to a hydrophobic property or from a hydrophobic property to a hydrophilic property under ultraviolet irradiation.

Optionally, in a specific implementation manner, in the array substrate provided in an embodiment of the present invention, the first pixel defining layer is made of azobenzene, spiropyran, cinnamic acid, titanium dioxide, or vanadium pentoxide; the material of the second pixel defining layer is an insulating material.

Optionally, in a specific implementation manner, in the array substrate provided in an embodiment of the present invention, a thickness of the first pixel defining layer is 100nm to 200nm, and a thickness of the second pixel defining layer is 50nm to 150 nm.

Optionally, in a specific implementation manner, in the array substrate provided in an embodiment of the present invention, the light-emitting function layer includes a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer, which are sequentially stacked.

Optionally, in a specific implementation, in the array substrate provided in an embodiment of the present invention, the hole injection layer and the electron transport layer are hydrophilic, and the hole transport layer and the light emitting layer are hydrophobic.

Optionally, in a specific implementation manner, in the array substrate provided in the embodiment of the present invention, the material of the light emitting layer is a quantum dot material.

Correspondingly, the embodiment of the invention also provides a display device which comprises the array substrate provided by the embodiment of the invention.

Correspondingly, the embodiment of the invention also provides a preparation method of the array substrate, which comprises the following steps:

forming a pixel defining layer having a plurality of opening regions on a substrate;

forming a light emitting function layer in each of the opening regions; wherein a portion of the pixel defining layer in contact with the light emitting function layer has a function of switching between hydrophilicity and hydrophobicity under a change in external conditions.

Optionally, in a specific implementation, in the preparation method provided in an embodiment of the present invention, the forming a pixel defining layer having a plurality of opening regions on a substrate includes:

spin-coating a first photoresist on the substrate base plate, and forming a patterned first photoresist layer after exposing and developing the first photoresist;

preparing a first pixel defining material layer on the substrate base plate with the first photoresist layer in a spin coating mode;

stripping the first photoresist layer to remove the first photoresist layer and the first pixel defining material layer above the first photoresist layer to form a plurality of pixel defining structures surrounding each opening region and independent of each other, each pixel defining structure constituting the first pixel defining layer;

depositing a film layer of insulating material on the first pixel defining layer at a side away from the substrate base plate;

patterning the insulating material film layer to expose each opening region so as to form a second pixel defining layer; the second pixel defining layer covers the plurality of pixel defining structures, the structure of the second pixel defining layer is a grid-shaped structure exposing each opening region, and the second pixel defining layer is used for insulating adjacent pixel defining structures from each other.

Optionally, in a specific implementation, in the preparation method provided in an embodiment of the present invention, forming a light-emitting functional layer in each of the opening regions specifically includes:

processing the substrate base plate on which the second pixel defining layer is formed under a first external condition to make the first pixel defining layer hydrophobic;

forming a hole injection layer in each opening region by adopting an ink-jet printing process;

processing the substrate base plate with the hole injection layer under a second external condition to make the first pixel defining layer hydrophilic;

forming a hole transport layer on one side of the hole injection layer, which is far away from the substrate base plate, by adopting an ink-jet printing process;

forming a light-emitting layer on one side of the hole transport layer, which is far away from the substrate base plate, by adopting an ink-jet printing process;

processing the substrate on which the light emitting layer is formed under the first external condition to make the first pixel defining layer hydrophobic;

and forming an electron transmission layer on one side of the light-emitting layer, which is far away from the substrate base plate, by adopting an ink-jet printing process.

The embodiment of the invention has the following beneficial effects:

in the array substrate, the manufacturing method thereof and the display device provided by the embodiments of the invention, the portion of the pixel defining layer in contact with the light-emitting function layer is configured to have a function of switching between hydrophilicity and hydrophobicity under the change of external conditions, so that when each film layer of the light-emitting function layer is formed, because the hydrophilicity and hydrophobicity of each film layer of the light-emitting function layer are different, if the hydrophilic light-emitting function layer is formed, the portion of the pixel defining layer in contact with the light-emitting function layer is switched to be hydrophobic under the external condition treatment, and when the hydrophobic light-emitting function layer is formed, the portion of the pixel defining layer in contact with the light-emitting function layer is switched to be hydrophilic under the external condition treatment, so that the light-emitting function layer formed in the opening area can not climb to the inner wall of the pixel defining layer, and the thickness of the light-emitting function layer formed in the opening area is uniform, the display effect of the display panel and the service life of the light-emitting device are improved.

Drawings

Fig. 1 is a schematic top view of an array substrate according to an embodiment of the present invention;

fig. 2A is a schematic structural diagram of an array substrate according to an embodiment of the invention;

FIG. 2B is a schematic top view of a pixel defining layer according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a light-emitting functional layer according to an embodiment of the present invention;

fig. 4 is a second schematic structural diagram of an array substrate according to an embodiment of the invention;

fig. 5 is a schematic structural diagram illustrating a light emitting function layer formed on the array substrate according to an embodiment of the present invention when no external condition treatment is performed;

fig. 6 is a second schematic structural view illustrating a light emitting functional layer formed on the array substrate according to the embodiment of the present invention when no external condition treatment is performed;

fig. 7A is a schematic structural diagram of a display device according to an embodiment of the present invention;

fig. 7B is a schematic structural diagram of a display device according to an embodiment of the present invention;

fig. 7C is a schematic structural diagram of a display device according to an embodiment of the invention;

fig. 8 is a schematic structural diagram of an array substrate provided in an embodiment of the invention when irradiated by ultraviolet light;

fig. 9 is a second schematic structural view of the array substrate according to the embodiment of the invention when the array substrate is placed in a dark place;

fig. 10 is a schematic flow chart illustrating a method for manufacturing an array substrate according to an embodiment of the invention;

fig. 11 is a second schematic flow chart illustrating a method for manufacturing an array substrate according to an embodiment of the invention;

fig. 12 is a third schematic flow chart illustrating a manufacturing method of an array substrate according to an embodiment of the invention;

fig. 13A to 13I are schematic cross-sectional views illustrating a method for fabricating an array substrate according to an embodiment of the invention after performing various steps;

fig. 14 is a schematic structural diagram of a display device according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The shapes and sizes of the various elements in the drawings are not to scale and are merely intended to illustrate the invention.

Embodiments of an array substrate, a method for manufacturing the array substrate, and a display device according to embodiments of the present invention are described in detail below with reference to the accompanying drawings.

An array substrate provided by an embodiment of the present invention is shown in fig. 1 and 2A, where fig. 1 is a schematic top view structure of the array substrate, fig. 2A is a schematic cross-sectional view along AA in fig. 1, the array substrate includes a substrate 1, a pixel defining layer 2 located on one side of the substrate 1, the pixel defining layer 2 has a plurality of opening regions 3, each opening region 3 includes a light emitting functional layer 4, and a portion (a first pixel defining layer 21, described in detail later) of the pixel defining layer 2, which is in contact with the light emitting functional layer 4, has a function of switching between hydrophilicity and hydrophobicity under a change of an external condition.

In the array substrate provided by the embodiment of the present invention, the portion of the pixel defining layer 2 in contact with the light-emitting function layer 4 is configured to have a function of switching between hydrophilicity and hydrophobicity under the change of external conditions, so that when each film layer of the light-emitting function layer 4 is formed, because each film layer of the light-emitting function layer 4 has different hydrophilicity and hydrophobicity, if the hydrophilic light-emitting function layer 4 is formed, the portion of the pixel defining layer 2 in contact with the light-emitting function layer 4 is switched to be hydrophobic under the external condition treatment, and when the hydrophobic light-emitting function layer 4 is formed, the portion of the pixel defining layer 2 in contact with the light-emitting function layer 4 is switched to be hydrophilic under the external condition treatment, so that the light-emitting function layer 4 formed in the opening region 3 does not climb to the inner wall of the pixel defining layer 2, and the thickness of the light-emitting function layer 4 formed in the opening region 3 is uniform, the display effect of the display panel and the service life of the light-emitting device are improved.

It should be noted that the substrate of the array substrate provided in the embodiment of the present invention is a substrate including a plurality of anodes corresponding to each opening region one to one, and generally, a metal film layer is deposited on the substrate, the metal film layer is patterned to form a plurality of anodes, a pixel defining film layer is spin-coated on the substrate on which the plurality of anodes are formed, the pixel defining film layer is patterned to form a pixel defining layer exposing the plurality of anodes, the exposed anode region is an opening region, and then a light emitting function layer, a cathode and a subsequent film layer are prepared; specifically, the anode material includes a transparent conductive material or a translucent conductive material. The details of the present invention for fabricating the pixel definition layer are described below.

In practical implementation, in the above array substrate provided by the embodiment of the present invention, since the organic electroluminescent device has both bottom emission and top emission, a bottom emission device structure is formed by providing an anode having transparency and a reflective cathode structure, whereas a top emission device structure is formed by providing a transparent cathode and a reflective anode structure. Therefore, the choice of the anode material is different according to the structure of the device, and the anode material is usually a transparent or semitransparent material with high work function such as ITO, Ag, NiO, Al, graphene, etc.

In practical implementation, in the array substrate provided in the embodiment of the present invention, as shown in fig. 3, the light-emitting functional layer 4 includes a hole injection layer 41, a hole transport layer 42, a light-emitting layer 43, and an electron transport layer 44, which are sequentially stacked. When the display device of the array substrate provided by the embodiment of the invention is of a positive structure, a hole injection layer 41 is formed on a substrate 1, and then a hole transport layer 42, a light emitting layer 43 and an electron transport layer 44 are sequentially formed; when the display device of the array substrate provided by the embodiment of the invention is an inverted structure, the electron transport layer 44 is formed on the substrate 1, and then the light emitting layer 43, the hole transport layer 42, and the hole injection layer 41 are sequentially formed. Of course, in practical implementation, the light-emitting functional layer 4 may further include an electron injection layer, and the embodiment of the present invention is described by taking an example in which the light-emitting functional layer 4 includes the hole injection layer 41, the hole transport layer 42, the light-emitting layer 43, and the electron transport layer 44.

Specifically, in the array substrate provided in the embodiment of the present invention, the light-emitting layer at least includes: a red light emitting layer, a green light emitting layer, and a blue light emitting layer. In addition, a white light emitting layer may be included, which is determined according to a specific arrangement of the pixels and is not particularly limited herein.

In practical implementation, in order to improve the light emitting efficiency of the device, in the array substrate provided by the embodiment of the invention, the material of the light emitting layer may be a quantum dot material. The quantum dot material can be binary, ternary or multi-element quantum dot luminescent material, which is not listed here.

In practical implementation, in the array substrate provided by the embodiment of the present invention, as shown in fig. 3, the hole injection layer 41 and the electron transport layer 44 are hydrophilic, and the hole transport layer 42 and the light emitting layer 43 are hydrophobic. Specifically, in the embodiment of the present invention, an inkjet printing process is adopted to form the hole injection layer 41, the hole transport layer 42, the light emitting layer 43, and the electron transport layer 44, and the ink states (i.e., liquid states) corresponding to the hole injection layer 41, the hole transport layer 42, the light emitting layer 43, and the electron transport layer 44 and the hydrophilicity and hydrophobicity of the solid state after drying are unchanged, for example, the liquid hole injection layer 41 and the electron transport layer 44 are hydrophilic, and the solid hole injection layer 41 and the electron transport layer 44 are still hydrophilic; the liquid hole transport layer 42 and the light emitting layer 43 are hydrophobic, and the solid hole transport layer 42 and the light emitting layer 43 are still hydrophobic.

In particular, due to the non-uniform hydrophilicity and hydrophobicity of the hole injection layer, the hole transport layer, the light emitting layer, and the electron transport layer, when each film layer of the light emitting function layer is formed by an inkjet printing process, a thin film (thick at both sides and thin in the middle) with non-uniform thickness is easily formed due to the magnanite effect, a thin film layer is easily formed in the middle of an opening region, and breakdown may be caused in a final device due to high voltage. Therefore, the invention provides a pixel defining layer, which can make the film thickness of each film layer of the formed light-emitting function layer uniform, and improve the light-emitting efficiency and the service life of a display device.

Specifically, hydrophilicity refers to a property having an affinity for water. Hydrophobic refers to the property of having a repellent ability to water. The hole injection layer and the electron transport layer are hydrophilic, and the contact angles between the hole injection layer and the electron transport layer and water are generally less than 50 degrees; the hole transport layer and the light-emitting layer are hydrophobic, and the contact angles of the hole transport layer and the light-emitting layer with water are generally larger than 120 degrees.

The following describes in detail the pixel defining layer provided by the embodiment of the present invention, which can make the film thickness of each film layer of the formed light emitting function layer uniform.

In practical implementation, as shown in fig. 2A and 2B, fig. 2B is a schematic top view of a pixel defining layer in the array substrate provided in the embodiment of the present invention, the pixel defining layer 2 includes a first pixel defining layer 21 and a second pixel defining layer 22 located on a side of the first pixel defining layer 21 away from the substrate 1;

the first pixel defining layer 21 includes a plurality of pixel defining structures 01 surrounding each of the opening regions 3 and independent of each other, the pixel defining structures 01 being in contact with the light emitting function layer 4; specifically, since the first pixel defining layer 21 is a portion in contact with the light emitting function layer 4, the first pixel defining layer 21 has a function of switching between hydrophilicity and hydrophobicity under a change in external conditions, and generally, most of materials having the function of switching between hydrophilicity and hydrophobicity are semiconductor materials, that is, the material of the first pixel defining layer 21 is a semiconductor material having a certain conductive capability, and since the first pixel defining layer 21 is in contact with both an anode and a cathode, the first pixel defining layer 21 is likely to have a short between adjacent opening regions 3 (i.e., sub-pixels) to cause a phenomenon of electric leakage between pixels, and thus, in order to prevent the short between the adjacent sub-pixels, the first pixel defining layer 21 is configured to include a plurality of pixel defining structures 01 surrounding each opening region 3 and independent of each other, so that the short problem between adjacent opening regions 3 does not occur;

as shown in fig. 2B, the second pixel defining layer 22 covers the plurality of pixel defining structures 01, the second pixel defining layer 22 has a grid structure exposing each opening region 3, and the second pixel defining layer 22 is used for insulating adjacent pixel defining structures 01 from each other. Specifically, since the pixel defining structures 01 of the first pixel defining layer 21 are independent from each other, if the light emitting function layer 4 and the cathode are directly formed after the first pixel defining layer 21 is formed, since the cathode is generally configured to be disposed over the entire surface, that is, the cathode covers the first pixel defining layer 21, a short problem still occurs between adjacent opening regions 3, and therefore, in the embodiment of the present invention, the second pixel defining layer 22 is further formed on the side of the first pixel defining layer 21 away from the substrate 1, so as to insulate the adjacent pixel defining structures 01 from each other. In the present invention, the cathode may be provided independently, but the present invention is not limited thereto.

In practical implementation, as shown in fig. 4, for clarity, fig. 4 only illustrates a part of the structure in fig. 2A, and a thickness D1 of the pixel defining structure 01 is greater than a thickness D2 of the light-emitting functional layer 4 along a direction from the substrate 1 to the pixel defining layer 2 in the array substrate provided by the embodiment of the present invention. Each film layer forming the light-emitting function layer 4 by adopting the ink-jet printing process is located in the pixel defining structure 01, and because the hydrophilicity and hydrophobicity of each film layer of the light-emitting function layer 4 are not consistent, each film layer forming the light-emitting function layer 4 can utilize the function of the first pixel defining layer 21 capable of converting between hydrophilicity and hydrophobicity under the external condition, for example, when the film layer of the light-emitting function layer 4 is hydrophilic, the first pixel defining layer 21 is converted into hydrophobicity under the external condition, and when the film layer of the light-emitting function layer 4 is hydrophobic, the first pixel defining layer 21 is converted into hydrophilicity under the external condition, so that the phenomenon that each film layer of the light-emitting function layer 4 climbs towards the inner wall of the first pixel defining layer 21 is avoided, and the film layers of the formed light-emitting function layer 4 are uniform in thickness.

In a specific implementation, in the array substrate provided in the embodiments of the present invention, the first pixel defining layer may be changed from a hydrophilic property to a hydrophobic property under the irradiation of ultraviolet light, or the first pixel defining layer may be changed from a hydrophobic property to a hydrophilic property under the irradiation of ultraviolet light. This property is described in detail later in connection with specific materials.

In a specific implementation, in the array substrate provided in the embodiment of the present invention, the material of the first pixel defining layer may be azobenzene, spiropyran, cinnamic acid, titanium dioxide, or vanadium pentoxide, and the five materials for example are all in a neutral state without being subjected to external condition treatment, and are neither hydrophilic nor hydrophobic; the material of the second pixel defining layer is an insulating material, such as SiO, SiN, etc. Specifically, as shown in fig. 5, taking the material of the first pixel defining layer 21 as titanium dioxide and the material of the second pixel defining layer 22 as SiO for example, when the titanium dioxide is in a neutral state without being subjected to external condition treatment, when the hole injection layer 41 is formed by an inkjet printing process, since the hole injection layer 41 is hydrophilic, the hydrophilic hole injection layer 41 climbs towards the inner wall of the first pixel defining layer 21 due to the magnanite effect, so that the middle of the formed hole injection layer 41 is thin and both sides of the formed hole injection layer are thick, and the film thickness of the formed hole injection layer 41 is not uniform, which affects the efficiency and the service life of the display device; as shown in fig. 6, fig. 6 is different from fig. 5 only in that a hydrophobic film layer such as a hole transport layer 42 is formed by an inkjet printing process, and since the hole transport layer 42 is hydrophobic, the hydrophobic hole transport layer 42 also climbs towards the inner wall of the first pixel defining layer 21 due to the magnanium effect, resulting in a phenomenon that the middle of the formed hole transport layer 42 is thin and both sides are thick, so that the film thickness of the formed hole transport layer 42 is not uniform, which affects the efficiency and the lifetime of the display device. Therefore, in order to solve the problem that the formed film layers are not uniform due to the non-uniform hydrophilicity and hydrophobicity of the film layers of the light-emitting functional layer 4, the first pixel defining layer 21 is processed under external conditions to be converted into hydrophilicity or hydrophobicity, and the hydrophilicity and hydrophobicity of the formed film layer of the light-emitting functional layer 4 is opposite to the hydrophilicity and hydrophobicity of the first pixel defining layer 21, so that the formed film layer of the light-emitting functional layer 4 can be uniform, and the efficiency and the service life of the light-emitting device can be improved.

Specifically, the external conditions in the embodiment of the present invention may be: ultraviolet light irradiation, visible light irradiation (such as blue light), heating, darkroom placement, etc.

Specifically, as shown in FIG. 7A, a film formed using azobenzene was exposed to ultraviolet light hv₁(for example, the wavelength is 365nm) presents a cis-structure under the irradiation, the surface hydrophilic state can be achieved when the polarity is increased, and the contact angle with water can reach 15 degrees; after the completion of the ultraviolet irradiation, the azobenzene film is heated (Delta) or subjected to visible light hv₂When the azobenzene is irradiated (such as blue light), the azobenzene can be changed into a trans structure, the polarity is reduced, the hydrophobic characteristic is presented, and the contact angle with water reaches 70 degrees.

Specifically, as shown in FIG. 7B, spiropyrans are exposed to ultraviolet light hv₁Hydrophobic after irradiation, heating (. DELTA.) or visible hv₂After irradiation, chemical bonds are broken, and hydrophilicity is exhibited.

Specifically, as shown in figure 7C, cinnamic acid was observed at UV hv₁After irradiation, the material shows hydrophilicity and shows visible light hv₂After irradiation, dimerization occurs, and hydrophobicity is exhibited.

Specifically, titanium dioxide (TiO2) was hydrophilic after irradiation with ultraviolet light and hydrophobic after 24 hours of dark room standing.

Specifically, vanadium pentoxide (VO5) exhibits hydrophilicity after ultraviolet irradiation and hydrophobicity after being left in a dark room for 24 hours.

Specifically, as shown in fig. 8, taking the material of the first pixel defining layer 21 as titanium dioxide (TiO2) and the material of the second pixel defining layer 22 as SiO for example, under ultraviolet light irradiation (UV irradiation), titanium dioxide is converted into a surface hydrophilic state, and thus the first pixel defining layer 21 can be irradiated with UV before the hydrophobic hole transport layer 42 and the light emitting layer 43 are formed; as shown in fig. 9, taking the material of the first pixel defining layer 21 as titanium dioxide (TiO2) and the material of the second pixel defining layer 22 as SiO for example, when the structure of fig. 9 is placed in the dark (for example, for 24 hours), the titanium dioxide is converted into a surface hydrophobic state, so that the structure of fig. 9 can be placed in the dark before the hydrophilic hole injection layer 41 and the hydrophilic electron transport layer 44 are formed to make the first pixel defining layer 21 hydrophobic.

Therefore, the five materials for manufacturing the first pixel defining layer provided in the embodiment of the present invention all have the reversible changes in hydrophilicity and hydrophobicity under external conditions, and how to form each film layer of the light emitting functional layer with inconsistent hydrophilicity and hydrophobicity by using the reversible changes is described in detail in the following preparation method.

In a specific implementation, in the array substrate provided in the embodiments of the present invention, the thickness of the first pixel defining layer may be 100nm to 200nm, and the thickness of the second pixel defining layer may be 50nm to 150 nm.

In a specific implementation, in the array substrate provided in the embodiment of the present invention, the thickness of the light-emitting functional layer may be 100nm to 200nm, and during the manufacturing process, it is only required to ensure that the thickness of the first pixel defining layer is greater than the thickness of the light-emitting functional layer.

Based on the same inventive concept, an embodiment of the present invention further provides a method for manufacturing an array substrate, as shown in fig. 10, including:

s1001, forming a pixel defining layer with a plurality of opening areas on a substrate;

s1002, forming a light-emitting functional layer in each opening region; wherein a portion of the pixel defining layer in contact with the light emitting functional layer has a function of switching between hydrophilicity and hydrophobicity under a change in external conditions.

In the method for manufacturing the array substrate according to the embodiment of the invention, the portion of the pixel defining layer, which is in contact with the light-emitting functional layer, is configured to have a function of switching between hydrophilicity and hydrophobicity under the change of external conditions, so that when each film layer of the light-emitting functional layer is formed, because the hydrophilicity and the hydrophobicity of each film layer of the luminous functional layer are not consistent, when the hydrophilic luminous functional layer is formed, the pixel defining layer is converted to be hydrophobic at a portion in contact with the light emitting function layer under an external condition treatment, when a hydrophobic light-emitting functional layer is formed, the pixel defining layer is converted into hydrophilic property at a portion in contact with the light-emitting functional layer under an external condition treatment, so that the light emitting function layer formed in the opening region does not climb to the inner wall of the pixel defining layer, therefore, the thickness of the luminous functional layer formed in the opening region is uniform, and the display effect of the display panel and the service life of the light-emitting device are improved.

In practical implementation, in the above manufacturing method provided by the embodiment of the present invention, as shown in fig. 11, forming a pixel defining layer having a plurality of opening regions on a substrate specifically includes:

s1101, spin-coating a first photoresist on a substrate, and exposing and developing the first photoresist to form a patterned first photoresist layer; specifically, as shown in fig. 13A, a first photoresist is spin-coated on the substrate base plate 1 on which the anode is formed, and the first photoresist is exposed and developed to form a patterned first photoresist layer 5.

S1102, preparing a first pixel defining material layer on the substrate with the first photoresist layer in a spin coating mode; specifically, as shown in fig. 13B, an azobenzene material layer 6 is spin-coated on the base substrate 1 on which the first photoresist layer 5 is formed, for example.

S1103, stripping the first photoresist layer to remove the first photoresist layer and the first pixel defining material layer on the first photoresist layer, so as to form a plurality of pixel defining structures surrounding each opening region and independent of each other, wherein each pixel defining structure constitutes a first pixel defining layer; specifically, as shown in fig. 13C, the first photoresist layer 5 is stripped to remove the first photoresist layer 5 and the titanium dioxide material layer 6 above the first photoresist layer 5, so as to form a plurality of pixel defining structures 01 surrounding each opening region 3 and independent of each other, each pixel defining structure 01 constituting the first pixel defining layer 21.

S1104, depositing an insulating material film layer on one side, away from the substrate, of the first pixel defining layer; specifically, as shown in fig. 13D, a PECVD process is used to deposit the insulating material film layer 7 on the side of the first pixel defining layer 21 away from the substrate base plate 1.

S1105, patterning the insulating material film layer to expose each opening region to form a second pixel defining layer; the second pixel defining layer covers the plurality of pixel defining structures, the structure of the second pixel defining layer is a grid-shaped structure with exposed opening areas, and the second pixel defining layer is used for insulating the adjacent pixel defining structures from each other; specifically, as shown in fig. 13E, the insulating material film layer 7 is patterned to expose each of the opening regions 3, so as to form a second pixel defining layer 22 which covers the plurality of pixel defining structures 01 and has a grid-like structure.

In practical implementation, in the above manufacturing method provided by the embodiment of the present invention, as shown in fig. 12, forming a light emitting functional layer in each opening region specifically includes:

s1201, processing the substrate base plate with the second pixel defining layer under a first external condition to enable the first pixel defining layer to be hydrophobic; specifically, since the film formed of azobenzene is hydrophilic under irradiation of ultraviolet light (e.g., 365nm in wavelength) and hydrophobic under irradiation of heat or visible light (e.g., blue light), the substrate 1 on which the second pixel defining layer 22 is formed is processed under the first external condition, that is, the substrate 1 on which the second pixel defining layer 22 is formed is irradiated with heat or visible light (e.g., blue light) for 1 to 30 minutes, so that the first pixel defining layer 21 is hydrophobic.

S1202, forming a hole injection layer in each opening region by adopting an ink-jet printing process; specifically, as shown in fig. 13F, a hydrophilic hole injection layer 41 is formed in each opening region 3 using an inkjet printing process.

S1203, processing the substrate with the hole injection layer under a second external condition to make the first pixel defining layer hydrophilic; specifically, the base substrate 1 on which the hole injection layer 41 is formed is treated under the second external condition, that is, the base substrate 1 on which the hole injection layer 41 is formed is irradiated under ultraviolet light (for example, wavelength of 365nm) for 1 to 30 minutes in a hydrophilic manner, so that the first pixel defining layer is rendered hydrophilic.

S1204, forming a hole transport layer on one side, away from the substrate, of the hole injection layer by adopting an ink-jet printing process; specifically, as shown in fig. 13G, a hydrophobic hole transport layer 42 is formed on the side of the hole injection layer 41 away from the base substrate by an inkjet printing process.

S1205, forming a light-emitting layer on one side, far away from the substrate, of the hole transport layer by adopting an ink-jet printing process; specifically, as shown in fig. 13H, a hydrophobic light-emitting layer 43 is formed on the hole transport layer 42 on the side away from the base substrate 1 by an ink-jet printing process.

S1206, processing the substrate with the light emitting layer under a first external condition to make the first pixel defining layer hydrophobic; specifically, the base substrate 1 on which the light-emitting layer 43 is formed is treated under a first external condition, that is, the base substrate 1 on which the light-emitting layer 43 is formed is irradiated with heat or visible light (e.g., 436nm blue light) for 1 to 30min to make the first pixel defining layer 21 hydrophobic.

S1207, forming an electron transmission layer on one side, far away from the substrate, of the light-emitting layer by adopting an ink-jet printing process; specifically, as shown in fig. 13I, a hydrophilic electron transport layer 44 is formed on the side of the light-emitting layer 43 away from the substrate 1 by an inkjet printing process, that is, the array substrate shown in fig. 2A of the present invention is formed.

In specific implementation, the array substrate shown in fig. 2A of the present invention is annealed, and then metal materials such as aluminum are deposited as a cathode, thereby completing the preparation of the OLED device.

With the deep development of quantum dot technology, the research of the electroluminescent quantum dot light-emitting diode is increasingly deep, and the quantum efficiency is continuously improved, so that the material of the light-emitting layer can be a quantum dot material, namely, a QLED device is formed.

In specific implementation, since the high-resolution QLED device can be manufactured by forming the light-emitting functional layer by using the inkjet printing technology, the embodiment of the present invention is described by taking the example of forming the light-emitting functional layer by using the inkjet printing technology, and the technical solution of the present invention is applicable to other processes such as vapor deposition to form the light-emitting functional layer, which is not limited in this respect.

In the method for manufacturing the array substrate according to the embodiment of the present invention, in fig. 13C, the first photoresist is exposed by using a positive photoresist, but in a specific implementation, the first photoresist may be exposed by using a negative photoresist, and a specific exposure manner is selected according to a practical application, and is not limited specifically herein.

It should be noted that, in the method for manufacturing the array substrate provided by the embodiment of the present invention, the patterning process may only include a photolithography process, or may include a photolithography process and an etching step, and may also include other processes for forming a predetermined pattern, such as printing, inkjet printing, and the like; the photolithography process is a process of forming a pattern by using a photoresist, a mask plate, an exposure machine, and the like, including processes of film formation, exposure, development, and the like. In particular implementations, the corresponding patterning process may be selected based on the structure formed in the present invention.

Based on the same inventive concept, the embodiment of the invention also provides a display device, which comprises the array substrate in the embodiment. Since the principle of the display device to solve the problem is similar to the aforementioned array substrate, the implementation of the display device can be referred to the implementation of the aforementioned array substrate, and repeated descriptions are omitted.

In specific implementation, as shown in fig. 14, the display device provided in the embodiment of the present invention may be: any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator, etc., is not limited herein.

In the array substrate, the manufacturing method thereof and the display device provided by the embodiments of the invention, the portion of the pixel defining layer in contact with the light-emitting function layer is configured to have a function of switching between hydrophilicity and hydrophobicity under the change of external conditions, so that when each film layer of the light-emitting function layer is formed, because the hydrophilicity and hydrophobicity of each film layer of the light-emitting function layer are different, if the hydrophilic light-emitting function layer is formed, the portion of the pixel defining layer in contact with the light-emitting function layer is switched to be hydrophobic under the external condition treatment, and when the hydrophobic light-emitting function layer is formed, the portion of the pixel defining layer in contact with the light-emitting function layer is switched to be hydrophilic under the external condition treatment, so that the light-emitting function layer formed in the opening area can not climb to the inner wall of the pixel defining layer, and the thickness of the light-emitting function layer formed in the opening area is uniform, the display effect of the display panel and the service life of the light-emitting device are improved.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.