CN111370459B

CN111370459B - Array substrate, manufacturing method thereof and display device

Info

Publication number: CN111370459B
Application number: CN202010209007.XA
Authority: CN
Inventors: 胡春静; 孙力; 尤娟娟
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2020-03-23
Filing date: 2020-03-23
Publication date: 2022-07-05
Anticipated expiration: 2040-03-23
Also published as: CN111370459A

Abstract

The invention relates to the technical field of display, and provides an array substrate, a manufacturing method thereof and a display device. The first blocking dams extend along the first direction and are distributed at intervals along the second direction; the second blocking dams extend along the second direction and are distributed at intervals along the first direction; the third blocking dams extend along the second direction and are distributed at intervals along the first direction, and a plurality of third blocking dams are arranged between every two adjacent second blocking dams; the third blocking dam at least partially located between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the plurality of different third blocking dams in the direction perpendicular to the substrate base plate increase in sequence in the first direction. The array substrate can solve the problem that the film thickness is uneven due to the inclination of the substrate when the pixel light-emitting unit is subjected to ink-jet printing.

Description

Array substrate, manufacturing method thereof and display device

Technical Field

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

Background

Compared with LCDs, organic electroluminescent devices (OLEDs) have the advantages of self-luminescence, fast response, wide viewing angle, high brightness, bright color, lightness and thinness, and are considered as next-generation display technologies. The organic electroluminescent device is generally formed by an inkjet printing technique in which a solution for forming an organic electroluminescent device is sprayed into an opening formed in a pixel defining layer. The thin film formed by the solution in the opening of the pixel defining layer has the problem of uneven thickness.

It is to be noted that the information invented in the above background section is only for enhancing the understanding of the background of the present invention, and therefore, may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The invention aims to provide an array substrate and a display device. The array substrate can solve the problem that the thickness of a thin film formed by a solution in an opening of a pixel definition layer is not uniform in the related art.

Additional features and advantages of the invention will be set forth in the detailed description which follows, or may be learned by practice of the invention.

According to an aspect of the present invention, there is provided an array substrate including: a substrate base plate and a pixel definition layer. The pixel defining layer is disposed on one side of the substrate base plate, and includes: the first blocking dams extend along a first direction and are distributed at intervals along a second direction, and the first direction is intersected with the second direction; the plurality of second blocking dams extend along the second direction and are distributed at intervals along the first direction; the plurality of third blocking dams extend along the second direction and are distributed at intervals along the first direction, and a plurality of third blocking dams are arranged between every two adjacent second blocking dams; wherein at least a part of the third blocking dams between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the plurality of different third blocking dams in the direction perpendicular to the substrate base plate increase in sequence in the first direction.

In an exemplary embodiment of the present invention, all of the third blocking dams located between two adjacent second blocking dams have different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the plurality of different third blocking dams in the direction perpendicular to the substrate base plate increase sequentially in the first direction.

In an exemplary embodiment of the present invention, the same number of the third dam is disposed between every two adjacent second dam.

In an exemplary embodiment of the present invention, 2 to 14 third dam bars are disposed between every two adjacent second dam bars.

In one exemplary embodiment of the present invention, a thickness of the first blocking dam in a direction perpendicular to the substrate base plate is equal to a thickness of the second blocking dam in a direction perpendicular to the substrate base plate.

In an exemplary embodiment of the invention, a thickness of any one of the third blocking dams in a direction perpendicular to the substrate base plate is smaller than a thickness of the first blocking dam in a direction perpendicular to the substrate base plate.

In one exemplary embodiment of the present invention, a thickness difference between adjacent third barrier dams having different thicknesses in a direction perpendicular to the substrate base plate is equal.

According to an aspect of the present invention, there is provided a method for manufacturing an array substrate, the method including:

forming a substrate base plate;

forming a pixel defining layer on one side of the substrate base plate;

wherein the pixel defining layer includes:

the first blocking dams extend along a first direction and are distributed at intervals along a second direction, and the first direction is intersected with the second direction;

the second blocking dams extend along the second direction and are distributed at intervals along the first direction;

the plurality of third blocking dams extend along the second direction and are distributed at intervals along the first direction, and a plurality of third blocking dams are arranged between every two adjacent second blocking dams;

wherein at least a part of the third blocking dams between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the plurality of different third blocking dams in the direction perpendicular to the substrate base plate increase in sequence in the first direction.

In one exemplary embodiment of the present invention, forming a pixel defining layer on one side of the substrate base plate includes:

coating a negative photoresist on one side of the substrate base plate, and forming a plurality of first blocking dams on the negative photoresist layer through a composition process;

and coating a negative photoresist on the same side of the substrate, and exposing and developing the negative photoresist through a half-tone mask plate to form the second blocking dam and the third blocking dam.

According to an aspect of the present invention, there is provided a display device including the array substrate.

The present disclosure provides an array substrate and a display device, the array substrate including: a substrate base plate and a pixel definition layer. The pixel defining layer is disposed on one side of the substrate base plate, and includes: the first blocking dams extend along a first direction and are distributed at intervals along a second direction, and the first direction is intersected with the second direction; the plurality of second blocking dams extend along the second direction and are distributed at intervals along the first direction; the plurality of third blocking dams extend along the second direction and are distributed at intervals along the first direction, and the plurality of third blocking dams are arranged between every two adjacent second blocking dams; wherein at least a part of the third blocking dams between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the plurality of different third blocking dams in the direction perpendicular to the substrate base plate increase in sequence in the first direction. The array substrate can solve the problem that a film formed by a solution in an opening of a pixel defining layer has uneven thickness.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a schematic structural diagram of an exemplary embodiment of an array substrate in the related art;

FIG. 2 is a schematic structural diagram of another exemplary embodiment of the related art;

fig. 3 is a schematic structural diagram of an exemplary embodiment of an array substrate according to the present disclosure;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3;

FIG. 5 is a schematic structural diagram of another exemplary embodiment of an array substrate according to the present disclosure;

FIG. 6 is a cross-sectional view taken along line A-A of FIG. 5;

fig. 7-9 are schematic views of a flow structure in an exemplary embodiment of a method for fabricating an array substrate according to the present disclosure;

fig. 10 is a schematic structural diagram of an exemplary embodiment of an array substrate according to the present disclosure.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

Although relative terms, such as "upper" and "lower," may be used in this specification to describe one element of an icon relative to another, these terms are used in this specification for convenience only, e.g., in accordance with the orientation of the examples described in the figures. It will be appreciated that if the device of the icon were turned upside down, the element described as "upper" would become the element "lower". Other relative terms, such as "high," "low," "top," "bottom," "left," "right," and the like are also intended to have similar meanings. When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via another structure.

The terms "a," "an," "the," and the like are used to denote the presence of one or more elements/components/parts; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.

Organic electroluminescent devices (OLEDs) typically include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. Portions of the film layers (e.g., hole injection layer, hole transport layer, light emitting layer) of the organic electroluminescent device (OLED) may be formed by inkjet printing techniques. The ink jet printing technique is to spray various fluid materials into pixel openings formed in a pixel definition layer to form corresponding film layers. The inkjet printing technology requires the fluid material to be sprayed into the pixel openings through a plurality of nozzles, however, the inkjet printing technology cannot guarantee that each nozzle sprays the exact same fluid material every time. Therefore, it is difficult to form a film layer with uniform thickness in different pixel openings, thereby causing non-uniform luminance of the organic electroluminescent device in each pixel opening. In addition, the size of the pixel opening is limited to be small, the fluidity of the fluid material in the pixel opening is poor, and a film layer with uniform thickness is difficult to form in the same pixel opening, thereby affecting the light emitting quality of the organic electroluminescent device. Meanwhile, due to the capillary action, the film layer formed in the pixel opening has the phenomenon that the thickness of the film layer is thin at the center and thick at the edge, so that the light-emitting quality of the organic electroluminescent device is further influenced.

To solve the above problem, fig. 1 shows a schematic structural diagram of an exemplary embodiment of an array substrate in the related art. The array substrate comprises a substrate 5 and a pixel defining layer positioned on one side of the substrate 5, wherein the pixel defining layer comprises a plurality of first blocking dams 1, a plurality of second blocking dams 2 and a plurality of third blocking dams 3, the plurality of first blocking dams 1 extend along a first direction Y and are distributed at intervals along a second direction X, and the first direction Y is different from the second direction X; a plurality of second blocking dams 2 extend along the second direction X and are distributed at intervals along the first direction Y; many third block dam 3 along second direction X extends, and follows first direction Y interval distribution, and every two are adjacent set up many between the second blocks dam 2 third blocks dam 3. The thicknesses of the first blocking dam 1 and the second blocking dam 2 in the direction perpendicular to the substrate base plate 5 are the same, and the thickness of the third blocking dam 3 in the direction perpendicular to the substrate base plate 5 is smaller than the thickness of the first blocking dam 1 in the direction perpendicular to the substrate base plate 5. A plurality of pixel regions 4, each including a plurality of pixel openings 6 therein, are formed adjacent to the first blocking dam 1 and adjacent to the second blocking dam 2. A plurality of pixel openings 6 in the same pixel region 4 may form organic electroluminescent devices of the same color. When the organic electroluminescent device is formed by using the ink-jet printing technology, fluid materials in the same pixel area 4 can flow between the pixel openings 6, so that the thickness of a film layer in each pixel opening in the same pixel area 4 is uniform. Since the pixel region 4 has a large size, the fluid material for forming the organic electroluminescent device can have a high fluidity in the same pixel region 4, so that a film layer having a more uniform thickness can be formed. In addition, since the pixel region 4 has a larger size, the capillary phenomenon is relatively reduced, thereby further forming a film layer with a more uniform thickness in the pixel region 4.

However, since the fluid material for forming the organic electroluminescent device in the same pixel region 4 may flow between the pixel openings 6 in the pixel region 4, when a printer stage or a VCD (Vacuum Cavity Dry) substrate for carrying the array substrate has a height difference in a vertical direction in the first direction Y or a direction opposite to the first direction Y, that is, when the printer stage or the VCD substrate is tilted in the first direction Y or the direction opposite to the first direction Y, the array substrate is also tilted in the first direction Y or the direction opposite to the first direction Y, and the fluid material in the same pixel region 4 flows to a side having a low height in the vertical direction, so as to form a film layer with uneven thickness. As shown in fig. 2, which is a schematic structural diagram of another exemplary embodiment of the related art, the pixel opening of the array substrate is filled with a fluid material, so that a film layer 7 is formed. When the array substrate is subjected to an inkjet printing process, and a printer table or a VCD substrate for carrying the array substrate is tilted in the first direction Y, as shown in fig. 2, the array substrate is also tilted in the first direction Y, and the height of the edge 51 of the substrate in the vertical direction is lower than the height of the edge 52 in the vertical direction. Therefore, in the same pixel region 4, the thickness of the film layer in the pixel opening near the edge 51 is greater than that in the pixel opening near the edge 52, which finally results in a larger difference in the light emitting luminance of each pixel opening.

Based on this, the present exemplary embodiment provides an array substrate, as shown in fig. 3 and 4, fig. 3 is a schematic structural diagram of an exemplary embodiment of the array substrate of the present disclosure, and fig. 4 is a cross-sectional view at a dotted line a-a in fig. 3. The array substrate includes: a base substrate 2, a pixel defining layer. A pixel defining layer is disposed at one side of the base substrate 2, the pixel defining layer including: the structure comprises a plurality of first blocking dams 11, a plurality of second blocking dams 12 and a plurality of third blocking dams 13, wherein the plurality of first blocking dams 11 extend along a first direction Y and are distributed at intervals along a second direction X, and the first direction Y is intersected with the second direction X; a plurality of second blocking dams 12 extend along the second direction X and are distributed at intervals along the first direction Y; the plurality of third blocking dams 13 extend along the second direction X and are distributed at intervals along the first direction Y, and a plurality of third blocking dams 13 are arranged between every two adjacent second blocking dams 12; as shown in fig. 4, all the third blocking dams 13 between two adjacent second blocking dams 12 have different thicknesses in a direction perpendicular to the substrate base plate 2, and the thicknesses of the plurality of different third blocking dams 13 in the direction perpendicular to the substrate base plate increase in sequence in the first direction.

In the array substrate provided by the present exemplary embodiment, as shown in fig. 3, two adjacent first blocking dams 11 and two adjacent second blocking dams 12 may enclose a plurality of pixel regions 3, each pixel region 3 includes a plurality of pixel openings 4, and the pixel openings 4 are closed loop openings formed by intersecting the first blocking dams 11, the two second blocking dams 12, and the third blocking dams 13. In the same pixel region 3, the third blocking dams 13 between adjacent pixel openings 4 have different thicknesses in a direction perpendicular to the substrate 2, and the thicknesses of the third blocking dams 13 in the direction perpendicular to the substrate increase in sequence in the first direction Y, so that in the same pixel region 3, the fluid material has different flow resistances between different pixel openings 4, wherein the higher the thickness of the third blocking dam 13 in the direction perpendicular to the substrate, the greater its resistance to the fluid material. In the same pixel region, the resistance to the flow of the fluid material in the first direction Y is greater, and the resistance to the flow of the fluid material in the direction opposite to the first direction Y is smaller. Therefore, when the array substrate is tilted in the first direction Y (i.e. the side 22 of the substrate 2 is lower in vertical height than the side 21), the flow resistance of the fluid material in the first direction Y in the same pixel region 3 is smaller and larger, so that the thickness of the film layer in each pixel opening 4 is more uniform; when the array substrate is tilted in the opposite direction of the first direction Y (i.e. the side 22 of the substrate 2 is higher in vertical height than the side 21), the flow resistance of the fluid material in the opposite direction of the first direction Y in the same pixel region 3 is reduced from large to small, so that the thickness of the film layer in each pixel opening 4 is more uniform.

In the present exemplary embodiment, as shown in fig. 3 and 4, 4 third blocking dams 13 may be disposed between every two adjacent second blocking dams 12. In the same pixel region 3, 4 third blocking dams 13 may partition the pixel region 3 into 5 pixel openings 4, and in the same pixel region 3, the same color of organic electroluminescent device material may be filled. It should be understood that, in other embodiments, another number of third blocking dams 13 may be disposed between every two adjacent second blocking dams 12, and the number of third blocking dams 13 disposed between two adjacent second blocking dams 12 may be the same or different.

In the present exemplary embodiment, 2 to 14 third blocking dams, for example, 2, 4, 5, 14 third blocking dams, etc., may be disposed between two adjacent second blocking dams. The thickness difference between the adjacent third blocking dams with different thicknesses in the direction perpendicular to the substrate base plate can be equal, so that the fluid resistance of the fluid in the first direction Y or the direction opposite to the first direction Y is uniform in change, and a more uniform film layer is formed.

In the present exemplary embodiment, as shown in fig. 4, the thickness of the first blocking dam 11 in the direction perpendicular to the substrate base plate 2 may be equal to the thickness of the second blocking dam 12 in the direction perpendicular to the substrate base plate. The thickness of any of the third barrier dams 13 in the direction perpendicular to the substrate base plate 2 may be smaller than the thickness of the first barrier dam 11 in the direction perpendicular to the substrate base plate. The first and

second blocking dams

11 and 12 have a high thickness so as to prevent fluid material from flowing between the respective pixel regions 3.

In the present exemplary embodiment, the third blocking dam between two adjacent second blocking dams may have a different thickness in a direction perpendicular to the substrate base only in a portion, and the thickness of the third blocking dam in the direction perpendicular to the substrate base in the portion may increase in sequence in the first direction. As shown in fig. 5 and 6, fig. 5 is a schematic structural diagram of another exemplary embodiment of the array substrate of the present disclosure. Fig. 6 is a cross-sectional view taken at the broken line a-a in fig. 5. Wherein the dotted line a-a may extend along a first direction Y, the array substrate including: a base substrate 2, a pixel defining layer. A pixel defining layer is disposed at one side of the base substrate 1, the pixel defining layer including: the first blocking dams 11, the second blocking dams 12 and the third blocking dams (including the third blocking dams 131, 132, 133 and 134) extend along a first direction Y, the first blocking dams 11 are distributed at intervals along a second direction X, and the first direction Y is intersected with the second direction X; a plurality of second blocking dams 12 extend along the second direction X and are distributed at intervals along the first direction Y; a plurality of third blocking dams extend along the second direction X and are distributed at intervals along the first direction Y, and a plurality of third blocking dams may be disposed between every two adjacent second blocking dams 12, as shown in fig. 5 and 6, four third blocking dams 131, 132, 133, 134 may be disposed between every two adjacent second blocking dams 12; wherein, as shown in fig. 6, the third blocking dam 131 and the third blocking dam 132 have the same thickness in the direction perpendicular to the substrate base plate 2, the third blocking dam 133 and the third blocking dam 134 have the same thickness in the direction perpendicular to the substrate base plate 2, and the thickness of the third blocking dam 134 in the direction perpendicular to the substrate base plate 2 is greater than the thickness of the third blocking dam 131 in the direction perpendicular to the substrate base plate 2. This arrangement also achieves the technical effect that when the array substrate is tilted in the first direction Y or in the direction opposite to the first direction Y, the thickness of the film layer in each pixel opening 4 is more uniform.

The present exemplary embodiment further provides a method for manufacturing an array substrate, including:

forming a substrate base plate;

forming a pixel defining layer on one side of the substrate base plate;

wherein the pixel defining layer includes:

The array substrate manufacturing method can form the array substrate, and the technical characteristics and the working principle of the array substrate are explained in detail and are not repeated herein.

The present exemplary embodiment provides a method for forming a pixel defining layer, as shown in fig. 7 to 9, which are schematic flow structure diagrams in an exemplary embodiment of a method for manufacturing an array substrate according to the present disclosure. Forming a pixel defining layer at one side of the substrate base plate may include:

as shown in fig. 7, a negative photoresist is coated on one side of the base substrate 2, and the negative photoresist layer is formed into a plurality of first blocking dams 11 through a patterning process, which may include exposure, development, and etching.

As shown in fig. 8 and 9, a negative photoresist 5 is coated on the same side of the base substrate 2, and the negative photoresist is exposed and developed through a half-tone mask 6 to form the second blocking dam 12 and the third blocking dam 13, where the direction of the arrow is the light direction. The patterns of the second blocking dam 12 and the third blocking dam 13 are the same as the light-transmitting part 61 of the halftone mask, the halftone mask forms strip-shaped negative photoresists with different thicknesses through different light-transmitting parts 61, and the strip-shaped negative photoresists with different thicknesses can form the second blocking dam 12 and the third blocking dam 13.

It should be understood that in other exemplary embodiments, the pixel defining layer may also be formed in other manners, for example, may be formed through a one-time patterning process by a halftone mask.

In the present exemplary embodiment, as shown in fig. 10, a schematic structural diagram of an exemplary embodiment of an array substrate according to the present disclosure is shown. Forming the pixel definition layer on the side of the substrate may further comprise forming a planarization layer 7 on the side of the substrate 2, forming an anode layer 8 on the side of the planarization layer facing away from the substrate, and then forming the pixel definition layer on the side of the anode layer facing away from the substrate. Wherein, when the organic electroluminescent device is top-emitting, the anode layer may be a reflective metal layer, for example, formed of Ag, NiO, Al, etc.; when the organic electroluminescent device is bottom-emitting, the anode layer may be a transparent conductive layer, for example, formed of ITO, graphene, or the like.

The present exemplary embodiment also provides a display device including the array substrate described above. The display device can be a mobile phone, a television, a tablet computer and other display devices.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is to be limited only by the terms of the appended claims.

Claims

1. An array substrate, comprising:

a substrate base plate;

a pixel defining layer disposed at one side of the substrate base, the pixel defining layer including:

the plurality of third blocking dams extend along the second direction and are distributed at intervals along the first direction, and the plurality of third blocking dams are arranged between every two adjacent second blocking dams;

wherein at least a portion of the third blocking dams between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the third blocking dams having different thicknesses in the direction perpendicular to the substrate base plate increase in sequence in the first direction.

2. The array substrate of claim 1, wherein all of the third blocking dams between two adjacent second blocking dams have different thicknesses in a direction perpendicular to the substrate base plate, and a plurality of different third blocking dams have thicknesses in the direction perpendicular to the substrate base plate that sequentially increase in the first direction.

3. The array substrate of claim 1, wherein the same number of the third blocking dams are disposed between every two adjacent second blocking dams.

4. The array substrate of claim 1, wherein 2-14 third blocking dams are disposed between every two adjacent second blocking dams.

5. The array substrate of claim 1, wherein a thickness of the first blocking dam in a direction perpendicular to the substrate base plate is equal to a thickness of the second blocking dam in a direction perpendicular to the substrate base plate.

6. The array substrate of claim 2, wherein a thickness of any one of the third blocking dams in a direction perpendicular to the substrate base plate is smaller than a thickness of the first blocking dam in a direction perpendicular to the substrate base plate.

7. The array substrate of claim 1, wherein a thickness difference between adjacent third barrier dams having different thicknesses in a direction perpendicular to the substrate base is equal.

8. A manufacturing method of an array substrate is characterized by comprising the following steps:

forming a substrate base plate;

forming a pixel defining layer on one side of the substrate base plate;

wherein the pixel defining layer includes:

wherein at least a portion of the third blocking dams between two adjacent second blocking dams has different thicknesses in a direction perpendicular to the substrate base plate, and the thicknesses of the third blocking dams having different thicknesses in the direction perpendicular to the substrate base plate sequentially increase in the first direction.

9. The method for manufacturing an array substrate according to claim 8, wherein forming a pixel defining layer on one side of the substrate comprises:

10. A display device comprising the array substrate according to claims 1 to 7.