CN115513264A

CN115513264A - Display substrate, manufacturing method thereof and display device

Info

Publication number: CN115513264A
Application number: CN202211159029.5A
Authority: CN
Inventors: 陈登云; 单真真; 李良坚; 宋尊庆; 杨静; 张慧娟; 刘利宾; 刘政; 史世明
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2022-09-22
Filing date: 2022-09-22
Publication date: 2022-12-23

Abstract

The disclosure provides a display substrate, a manufacturing method thereof and a display device, and belongs to the technical field of display. Wherein, the display substrate includes: a drive substrate; a first electrode on the driving substrate; the pixel defining layer is positioned on one side of the first electrode, which is far away from the driving substrate; the isolation column is positioned on one side, away from the driving substrate, of the pixel defining layer, and the orthographic projection of the isolation column on the driving substrate is positioned in the orthographic projection of the pixel defining layer on the driving substrate; the organic light-emitting layer is positioned on one side of the isolation column, which is far away from the driving substrate, and the organic light-emitting layer is broken on the side surface of the isolation column; and the second electrode is positioned on one side of the organic light-emitting layer, which is far away from the driving substrate. The technical scheme of the disclosure can improve the pixel density of the display substrate.

Description

Display substrate, manufacturing method thereof and display device

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a display substrate, a manufacturing method thereof, and a display device.

Background

An Organic Light-Emitting Diode (OLED) display device has the advantages of being thin, light, wide in viewing angle, active in Emitting Light, continuously adjustable in Emitting color, low in cost, fast in response speed, low in energy consumption, low in driving voltage, wide in working temperature range, simple in production process, high in Light Emitting efficiency, flexible in display and the like, and is taken as a next generation display technology with great development prospects.

In the related art, pixels of the OLED display device are manufactured by an FMM (fine metal mask), which is costly and has a limitation in PPI (pixel density).

Disclosure of Invention

The technical problem to be solved by the present disclosure is to provide a display substrate, a manufacturing method thereof, and a display device, which can improve the pixel density of the display substrate.

In order to solve the above technical problem, embodiments of the present disclosure provide the following technical solutions:

in one aspect, a display substrate is provided, including:

a drive substrate;

a first electrode on the driving substrate;

the pixel defining layer is positioned on one side of the first electrode, which is far away from the driving substrate;

the isolation column is positioned on one side, away from the driving substrate, of the pixel defining layer, and the orthographic projection of the isolation column on the driving substrate is positioned in the orthographic projection of the pixel defining layer on the driving substrate;

the organic light-emitting layer is positioned on one side of the isolation column, which is far away from the driving substrate, and the organic light-emitting layer is broken on the side surface of the isolation column;

and the second electrode is positioned on one side of the organic light-emitting layer, which is far away from the driving substrate.

In some embodiments, at least one side of the spacer is formed with a notch.

In some embodiments, the isolation pillars are metal isolation pillars.

In some embodiments, the isolation pillar includes a first metal pattern and a second metal pattern stacked in a direction close to the driving substrate, and an orthogonal projection of the second metal pattern on the driving substrate is located within an orthogonal projection of the first metal pattern on the driving substrate.

In some embodiments, the isolation pillar further includes a third metal pattern located on a side of the second metal pattern close to the driving substrate, and an orthographic projection of the second metal pattern on the driving substrate is located within an orthographic projection of the third metal pattern on the driving substrate.

In some embodiments, the second electrode is a transparent conductive oxide.

In some embodiments, the pixel definition layer defines a plurality of open regions having a minimum width of no greater than 2um.

In some embodiments, the height of the isolation column is 0.5um to 3um.

Embodiments of the present disclosure provide a display device including the display substrate as described above.

An embodiment of the present disclosure provides a method for manufacturing a display substrate, including:

forming a driving substrate;

forming a first electrode on the driving substrate;

forming a pixel defining layer on one side of the first electrode far away from the driving substrate;

forming an isolation column on one side of the pixel defining layer far away from the driving substrate, wherein the orthographic projection of the isolation column on the driving substrate is positioned in the orthographic projection of the pixel defining layer on the driving substrate;

and forming an organic light-emitting layer and a second electrode on one side of the isolation column far away from the driving substrate, wherein the organic light-emitting layer is broken at the side surface of the isolation column.

In some embodiments, forming the isolation pillar comprises:

forming the isolation column with at least one circle of notches on at least one side surface.

In some embodiments, forming the isolation pillar comprises:

forming a second metal material layer on the driving substrate with the pixel defining layer formed thereon, and forming a first metal material layer on one side of the second metal material layer away from the driving substrate;

performing first etching on the first metal material layer and the second metal material layer to form an initial isolation column;

and carrying out wet etching on the initial isolation column, wherein the etching speed of the used etching liquid to the second metal material layer is higher than that to the first metal material layer, so that the notch is formed.

In some embodiments, forming the isolation pillar comprises:

sequentially forming a third metal material layer, a second metal material layer and a first metal material layer on the driving substrate on which the pixel defining layer is formed;

performing first etching on the third metal material layer, the second metal material layer and the first metal material layer to form an initial isolation column;

and carrying out wet etching on the initial isolation column, wherein the etching speed of the used etching liquid on the second metal material layer is higher than the etching speed on the first metal material layer and the etching speed on the third metal material layer, so that the notch is formed.

In some embodiments, the first etch is a dry etch.

In some embodiments, the pixel defining layer defines a plurality of pixel regions including a first color pixel region, a second color pixel region, and a third color pixel region, and the forming the organic light emitting layer and the second electrode on the side of the pillar away from the driving substrate includes:

sequentially depositing a first color organic light emitting layer and a second electrode layer on one side of the isolation column away from the driving substrate;

patterning the first color organic light emitting layer and the second electrode layer by adopting a photoetching process, and reserving the first color organic light emitting layer and the second electrode layer which are positioned in the first color pixel region;

depositing a second color organic light emitting layer and a second electrode layer on one side of the isolation column away from the driving substrate in sequence;

patterning the second color organic light emitting layer and the second electrode layer by adopting a photoetching process, and reserving the second color organic light emitting layer and the second electrode layer which are positioned in a second color pixel region;

depositing a third color organic light-emitting layer and a second electrode layer on one side of the isolation column away from the driving substrate in sequence;

and patterning the third color organic light emitting layer and the second electrode layer by adopting a photoetching process, and reserving the third color organic light emitting layer and the second electrode layer which are positioned in the third color pixel area.

The embodiment of the disclosure has the following beneficial effects:

in the scheme, the isolation column is arranged on one side of the pixel defining layer, which is far away from the driving substrate, and after the organic light emitting layer is formed on one side of the isolation column, which is far away from the driving substrate, the organic light emitting layer is broken on the side surface of the isolation column, so that the organic light emitting layers in different pixel areas can be separated, after the organic light emitting layers in different pixel areas are separated, the organic light emitting layer corresponding to one color pixel can be reserved, and the organic light emitting layers in other pixel areas can be removed through a photoetching process; therefore, the organic light emitting layers corresponding to various colors can be obtained through multiple photoetching processes, the organic light emitting layers of different colors can be manufactured through the photoetching processes, on one hand, the manufacturing cost of the display substrate is reduced, and on the other hand, the pixel density of the display substrate can be improved due to the fact that the photoetching processes are better in precision.

Drawings

Fig. 1a and 1b are schematic plan views of a display substrate according to an embodiment of the disclosure;

FIG. 2 is a schematic cross-sectional view of a substrate in the AA direction of FIG. 1 according to an embodiment of the present disclosure;

3 a-3 d are schematic structural views of an isolation column according to an embodiment of the disclosure;

fig. 4-17 are schematic flow charts illustrating a method for manufacturing a display substrate according to an embodiment of the disclosure.

Reference numerals

01 drive substrate

02 pixel definition layer

03 first electrode

04 isolating column

041 first metal pattern

042 second metal pattern

043 third metal pattern

05 organic light emitting layer of first color

06 second electrode layer

07 Photoresist

08 mask plate

09 organic light-emitting layer of a second color

10 organic light emitting layer of third color

11 encapsulation layer

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

Embodiments of the present disclosure provide a display substrate, a manufacturing method thereof, and a display device, which can improve pixel density of the display substrate.

An embodiment of the present disclosure provides a display substrate, including:

a drive substrate;

a first electrode on the driving substrate;

In this embodiment, the isolation pillar is disposed on a side of the pixel defining layer away from the driving substrate, and after the organic light emitting layer is formed on a side of the isolation pillar away from the driving substrate, the organic light emitting layer is broken at a side surface of the isolation pillar, so that the organic light emitting layers located in different pixel regions can be separated, after the organic light emitting layers in different pixel regions are separated, the organic light emitting layer corresponding to a color pixel can be retained, and the organic light emitting layers in other pixel regions can be removed through a photolithography process; therefore, the organic light emitting layers corresponding to various colors can be obtained through multiple photoetching processes, the organic light emitting layers with different colors can be manufactured through the photoetching processes, on one hand, the manufacturing cost of the display substrate is reduced, and on the other hand, the pixel density of the display substrate can be improved due to the fact that the photoetching process is better in precision.

In this embodiment, the driving substrate includes a substrate, and a thin film transistor array, a trace, and the like formed on the substrate. The substrate base plate can adopt a flexible substrate, such as a polyimide film; a hard substrate such as a quartz substrate or a glass substrate may also be used. The first electrode, the organic light-emitting layer and the second electrode form a light-emitting device, and the organic light-emitting layer can emit light under the action of an electric field between the first electrode and the second electrode.

In this embodiment, in order to completely separate the organic light emitting layers located in different pixel regions, isolation pillars may be disposed on the pixel defining layers between the different pixel regions to completely separate the pixel regions of different colors. As shown in fig. 1a, the display substrate includes a red pixel a, a green pixel G, and a blue pixel B, and an isolation pillar 04 is disposed between a pixel region where the red pixel R is located and a pixel region where the blue pixel B is located; isolation columns 04 are arranged between the pixel area where the red pixel R is located and the pixel area where the green pixel G is located; and the isolation columns 04 are arranged between the pixel area where the green pixel G is located and the pixel area where the blue pixel B is located.

Of course, the isolation pillars 04 may be disposed only in a partial region of the pixel defining layer 02, as shown in fig. 1 b.

In this embodiment, the longitudinal section of the isolation pillar may be rectangular, inverted trapezoid, or the like, as long as it can ensure that the organic light emitting layer is broken at the side of the isolation pillar, and after the organic light emitting layer is broken at the side of the isolation pillar, a second electrode located at a side of the organic light emitting layer away from the driving substrate is formed by a sputtering process. Specifically, the second electrode may employ a Transparent Conductive Oxide (TCO) including, but not limited to, ITZO, IZO, ITO, or the like, so as not to affect the light emission of the organic light emitting layer.

Since the thickness of the second electrode is generally thin, the resistance value of the second electrode is high, and the voltage drop (IR-drop) is severe when the display device is driven, which affects the uniformity of the display luminance of the display device. In this embodiment, the isolation column may be a metal isolation column, so that the isolation column may be reused as an auxiliary electrode structure, and multiple auxiliary electrode structures are connected in parallel with the second electrode, which may reduce the resistance of the second electrode, and thus may improve the IR-drop problem caused by the larger resistance of the second electrode. When the display substrate is applied to a display device, the uniformity of the display brightness of the display device can be ensured, and the display quality of the display device is improved.

In this embodiment, in order to ensure that the organic light emitting layer is broken at the side surface of the isolation pillar, as shown in fig. 2, a notch may be formed at least one side surface of the isolation pillar 04; a notch may be formed in a partial region of the side of the separation column 04; a circle of notches surrounding the isolation column 04 can also be formed on the side surface of the isolation column 04; one-turn notches may be formed in the side surfaces of the isolation pillars 04, or multiple-turn notches may be formed.

In some embodiments, as shown in fig. 3a, in a direction close to the driving substrate, the isolation pillar 04 includes a first metal pattern 041 and a second metal pattern 042, which are stacked, and an orthogonal projection of the second metal pattern 042 on the driving substrate is located within an orthogonal projection of the first metal pattern 041 on the driving substrate, so that a notch is formed at a side surface of the isolation pillar 04.

Specifically, a second metal material layer may be formed on a driving substrate on which a pixel defining layer is formed, and a first metal material layer may be formed on a side of the second metal material layer away from the driving substrate; performing a first etching on the first metallic material layer and the second metallic material layer to form an initial isolation pillar 040, as shown in fig. 3 b; and performing wet etching on the initial isolation pillars 040, wherein the etching speed of the second metal material layer by using etching liquid is higher than that of the first metal material layer, thereby forming the notch shown in fig. 3 a.

The first etching may be wet etching or dry etching.

When the materials of the first metal material layer and the second metal material layer are selected, the requirement that the etching rate of the second metal material layer in a specific etching liquid is greater than that of the first metal material layer in the specific etching liquid is met, when wet etching is adopted in first etching, the etching liquid used in first etching is not the specific etching liquid, and the etching rates of the first metal material layer and the second metal material layer in the etching liquid used in the first etching are the same or similar, so that a notch cannot be formed on the side face of the initial isolation column. After the initial isolation column is formed, wet etching is carried out on the initial isolation column, etching liquid used in the wet etching needs to meet the condition that the etching speed of the second metal material layer is higher than that of the first metal material layer, and therefore the etched part of the second metal material layer pattern is more than that of the first metal material layer pattern, and therefore the isolation column with the notches on the side face is formed. In a specific example, the etching solution used in the wet etching may have an etching effect only on the second metal material layer, and has no etching effect on the first metal material layer, so that after the initial isolation pillar 040 is wet-etched by using the etching solution, the pattern of the first metal material layer is retained, and the first metal pattern 041 is formed; the first metal pattern 041 and the second metal pattern 042 form an isolation pillar 04, and an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the first metal pattern 041 on the driving substrate, thereby forming a recess.

Specifically, the first metal material layer may adopt Ti, and the second metal material layer may adopt Al; alternatively, mo may be used for the first metallic material layer, and Al may be used for the second metallic material layer.

In some embodiments, as shown in fig. 3c, in a direction close to the driving substrate, the isolation pillar 04 includes a first metal pattern 041 and a second metal pattern 042 that are stacked, an orthogonal projection of the second metal pattern 042 on the driving substrate is located in an orthogonal projection of the first metal pattern 041 on the driving substrate, the isolation pillar 04 further includes a third metal pattern 043 located on a side of the second metal pattern 042 close to the driving substrate, and an orthogonal projection of the second metal pattern 042 on the driving substrate is located in an orthogonal projection of the third metal pattern 043 on the driving substrate, so that a notch is formed on a side surface of the isolation pillar 04.

Specifically, a third metal material layer may be formed on the driving substrate on which the pixel defining layer is formed, a second metal material layer may be formed on a side of the third metal material layer away from the driving substrate, and a first metal material layer may be formed on a side of the second metal material layer away from the driving substrate; performing a first etching on the third metal material layer, the second metal material layer and the first metal material layer to form an initial isolation pillar 040, as shown in fig. 3 d; and performing wet etching on the initial isolation pillar 040, wherein the etching speed of the used etching liquid on the second metal material layer is higher than that of the etching liquid on the first metal material layer, and the etching speed on the second metal material layer is higher than that of the etching liquid on the third metal material layer, so as to form the notch shown in fig. 3 c.

The first etching may be wet etching or dry etching.

When the materials of the third metal material layer, the first metal material layer and the second metal material layer are selected, it needs to be satisfied that the etching rate of the second metal material layer in a specific etching solution is greater than that of the first metal material layer in the specific etching solution, and the etching rate of the second metal material layer in the specific etching solution is greater than that of the third metal material layer in the specific etching solution. When wet etching is adopted in the first etching, the etching liquid used in the first etching is not the specific etching liquid, and the etching rates of the first metal material layer, the third metal material layer and the second metal material layer in the etching liquid used in the first etching are the same or similar, so that no notch is formed on the side surface of the initial isolation column. After the initial isolation column is formed, wet etching is carried out on the initial isolation column, etching liquid used in the wet etching needs to meet the condition that the etching speed of the second metal material layer is higher than that of the first metal material layer, the etching speed of the second metal material layer is higher than that of the third metal material layer, therefore, the etched part of the second metal material layer pattern is more than that of the first metal material layer pattern, and the etched part of the second metal material layer pattern is more than that of the third metal material layer pattern, so that the isolation column with the notches on the side surfaces is formed. In a specific example, the etching solution used in the wet etching may have an etching effect only on the second metal material layer, and has no etching effect on the first metal material layer and the third metal material layer, so that after the initial isolation pillar 040 is wet-etched by using the etching solution, the pattern of the first metal material layer is retained, and the first metal pattern 041 is formed; the third metal material layer pattern is reserved to form a third metal pattern 043; the first metal pattern 041, the second metal pattern 042 and the third metal pattern 043 form an isolation pillar 04, an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the first metal pattern 041 on the driving substrate, and an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the third metal pattern 043 on the driving substrate, so that a notch is formed.

Specifically, the first metal material layer may adopt Ti, the second metal material layer may adopt Al, and the third metal material layer may adopt Ti; alternatively, the first metal material layer may employ Mo, the second metal material layer may employ Al, and the third metal material layer may employ Mo.

The above-mentioned specific embodiment is described by taking an example that the isolation pillar includes a two-layer metal pattern and a three-layer metal pattern, but the isolation pillar of the present disclosure is not limited to include a two-layer metal pattern and a three-layer metal pattern, and may include more layers of metal patterns.

After at least one turn of the pillars 04 is formed by the above method, an organic light emitting layer may be formed, which is broken at the recesses of the pillars 04, so that the organic light emitting layers of different pixel regions may be separated.

In this embodiment, a plurality of opening regions are defined by the pixel defining layer, and since the organic light emitting layer can be manufactured by adopting a photolithography process, the pixel density of the display substrate can be improved, and the minimum width of the opening region can be not more than 2um, so that the pixel density of the display substrate can be effectively improved.

In some embodiments, the height of the isolation column is 0.5um to 3um, and when the thickness of the isolation column is in this range, the organic light emitting layer can be ensured to be broken at the side surface of the isolation column, and no obvious influence is caused on the thickness of the display substrate.

The display device includes but is not limited to: radio frequency unit, network module, audio output unit, input unit, sensor, display unit, user input unit, interface unit, memory, processor, and power supply. It will be appreciated by those skilled in the art that the above described configuration of the display device does not constitute a limitation of the display device, and that the display device may comprise more or less of the components described above, or some components may be combined, or a different arrangement of components. In the disclosed embodiments, the display device includes, but is not limited to, a display, a mobile phone, a tablet computer, a television, a wearable electronic device, a navigation display device, and the like.

The display device may be: the display device comprises a television, a display, a digital photo frame, a mobile phone, a tablet personal computer and any other product or component with a display function, wherein the display device further comprises a flexible circuit board, a printed circuit board and a back plate.

forming a driving substrate;

forming a first electrode on the driving substrate;

forming an isolation column on one side of the pixel defining layer, which is far away from the driving substrate, wherein the orthographic projection of the isolation column on the driving substrate is positioned in the orthographic projection of the pixel defining layer on the driving substrate;

and forming an organic light-emitting layer and a second electrode on one side of the isolation column far away from the driving substrate, wherein the organic light-emitting layer is broken on the side face of the isolation column.

In this embodiment, the driving substrate includes a substrate, and a thin film transistor array, a trace, and the like formed on the substrate. The substrate base plate can adopt a flexible substrate, such as a polyimide film; a hard substrate such as a quartz substrate or a glass substrate may also be used. The first electrode, the organic light-emitting layer and the second electrode form a light-emitting device, and the organic light-emitting layer can emit light under the action of an electric field between the first electrode and the second electrode. The organic light emitting Layer includes a Hole Injection Layer (HIL), a Hole Transport Layer (HTL), an Emission Layer (EML), an Electron Transport Layer (ETL), a Hole Blocking Layer (HBL), and an Electron Blocking Layer (EBL).

In this embodiment, in order to completely separate the organic light emitting layers located in different pixel regions, isolation pillars may be disposed on the pixel defining layers between the different pixel regions to completely separate the pixel regions of different colors. As shown in fig. 1a, the display substrate includes a red pixel a, a green pixel G and a blue pixel B, and an isolation pillar 04 is disposed between a pixel region where the red pixel R is located and a pixel region where the blue pixel B is located; isolation columns 04 are arranged between the pixel area where the red pixel R is located and the pixel area where the green pixel G is located; and the isolation columns 04 are arranged between the pixel area where the green pixel G is located and the pixel area where the blue pixel B is located.

In this embodiment, the longitudinal section of the isolation pillar may be rectangular, inverted trapezoid, or the like, as long as it is ensured that the organic light emitting layer is broken at the side surface of the isolation pillar, and after the organic light emitting layer is broken at the side surface of the isolation pillar, a sputtering process is used to form a second electrode located at a side of the organic light emitting layer away from the driving substrate. Specifically, the second electrode may employ a transparent conductive oxide including, but not limited to, ITZO, IZO, ITO, and the like.

Since the thickness of the second electrode is generally thin, the resistance value of the second electrode is high, and the voltage drop (IR-drop) is severe when the display device is driven, which affects the uniformity of the display luminance of the display device. In this embodiment, the isolation column may be a metal isolation column, so that the isolation column may be reused as an auxiliary electrode structure, and a plurality of auxiliary electrode structures are connected in parallel with the second electrode, which may reduce the resistance of the second electrode, thereby improving the IR-drop problem caused by the larger resistance of the second electrode. When the display substrate is applied to the display device, the uniformity of the display brightness of the display device can be ensured, and the display quality of the display device is improved.

In some embodiments, forming the isolation pillar comprises:

As shown in fig. 3a, in a direction approaching the driving substrate, the isolation pillar 04 includes a first metal pattern 041 and a second metal pattern 042, which are stacked, and an orthogonal projection of the second metal pattern 042 on the driving substrate is located within an orthogonal projection of the first metal pattern 041 on the driving substrate, so that a notch is formed at a side surface of the isolation pillar 04.

Specifically, a second metal material layer may be formed on the driving substrate on which the pixel defining layer is formed, and a first metal material layer may be formed on a side of the second metal material layer away from the driving substrate; performing a first etching on the first metallic material layer and the second metallic material layer to form an initial isolation pillar 040, as shown in fig. 3 b; and performing wet etching on the initial isolation pillars 040, wherein the etching speed of the second metal material layer by using etching liquid is higher than that of the first metal material layer, thereby forming the notch shown in fig. 3 a.

The first etching may be wet etching or dry etching.

When the materials of the first metal material layer and the second metal material layer are selected, the requirement that the etching rate of the second metal material layer in specific etching liquid is larger than that of the first metal material layer in the specific etching liquid is met, when wet etching is adopted in first etching, the etching liquid used in first etching is not the specific etching liquid, and the etching rates of the first metal material layer and the second metal material layer in the etching liquid used in the first etching are the same or similar, so that a notch cannot be formed on the side face of the initial isolation column. After the initial isolation column is formed, wet etching is carried out on the initial isolation column, etching liquid used in the wet etching needs to meet the condition that the etching speed of the second metal material layer is higher than that of the first metal material layer, so that the etched part of the second metal material layer pattern is more than that of the first metal material layer pattern, and the isolation column with the notch on the side face is formed. In a specific example, the etching solution used in the wet etching may have an etching effect only on the second metal material layer, and has no etching effect on the first metal material layer, so that after the initial isolation pillar 040 is wet-etched by using the etching solution, the pattern of the first metal material layer is retained, and the first metal pattern 041 is formed; the first metal pattern 041 and the second metal pattern 042 form an isolation pillar 04, and an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the first metal pattern 041 on the driving substrate, thereby forming a recess.

In some embodiments, forming the isolation pillar comprises:

and performing wet etching on the initial isolation column, wherein the etching speed of the used etching liquid to the second metal material layer is higher than the etching speed to the first metal material layer and the etching speed to the third metal material layer, so that the notch is formed.

As shown in fig. 3c, in a direction approaching the driving substrate, the isolation pillar 04 includes a first metal pattern 041 and a second metal pattern 042, which are stacked, an orthogonal projection of the second metal pattern 042 on the driving substrate is located in an orthogonal projection of the first metal pattern 041 on the driving substrate, the isolation pillar 04 further includes a third metal pattern 043 located on a side of the second metal pattern 042 near the driving substrate, and an orthogonal projection of the second metal pattern 042 on the driving substrate is located in an orthogonal projection of the third metal pattern 043 on the driving substrate, so that a notch is formed on a side surface of the isolation pillar 04.

The first etching may be wet etching or dry etching.

When the materials of the third metal material layer, the first metal material layer and the second metal material layer are selected, it needs to be satisfied that the etching rate of the second metal material layer in a specific etching solution is greater than that of the first metal material layer in the specific etching solution, and the etching rate of the second metal material layer in the specific etching solution is greater than that of the third metal material layer in the specific etching solution. When the first etching adopts wet etching, the etching liquid used by the first etching is not the specific etching liquid, and the etching rates of the first metal material layer, the third metal material layer and the second metal material layer in the etching liquid used by the first etching are the same or similar, so that a notch cannot be formed on the side surface of the initial isolation column. After the initial isolation column is formed, wet etching is carried out on the initial isolation column, etching liquid used in the wet etching needs to meet the condition that the etching speed of the second metal material layer is higher than that of the first metal material layer, the etching speed of the second metal material layer is higher than that of the third metal material layer, therefore, the etched part of the second metal material layer pattern is more than that of the first metal material layer pattern, and the etched part of the second metal material layer pattern is more than that of the third metal material layer pattern, so that the isolation column with the notches on the side surfaces is formed. In a specific example, the etching solution used in the wet etching may have an etching effect only on the second metal material layer, and has no etching effect on the first metal material layer and the third metal material layer, so that after the initial isolation pillar 040 is wet-etched by using the etching solution, the pattern of the first metal material layer is retained, and the first metal pattern 041 is formed; the third metal material layer pattern is reserved to form a third metal pattern 043; the first metal pattern 041, the second metal pattern 042 and the third metal pattern 043 form an isolation pillar 04, an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the first metal pattern 041 on the driving substrate, and an orthographic projection of the second metal pattern 042 on the driving substrate is located in an orthographic projection of the third metal pattern 043 on the driving substrate, so that a notch is formed.

Specifically, the first metal material layer may be Ti, the second metal material layer may be Al, and the third metal material layer may be Ti; alternatively, the first metal material layer may employ Mo, the second metal material layer may employ Al, and the third metal material layer may employ Mo.

In a specific example, the pixel defining layer defines a plurality of pixel regions including a first color pixel region, a second color pixel region and a third color pixel region, and as shown in fig. 4 to 17, the forming the organic light emitting layer and the second electrode on the side of the isolation pillar away from the driving substrate includes:

step 1, as shown in fig. 4, depositing a first color organic light emitting layer 05 on one side of the isolation column 04 away from the driving substrate 01;

wherein the first electrode 03 and the pixel defining layer 02 have been formed on the driving substrate. The first color organic light emitting layer 05 can be formed by evaporation or deposition, and the first color organic light emitting layer 05 is broken at the side surface of the isolation column 04 due to the notch formed at the side surface of the isolation column 04;

step 2, as shown in fig. 5, forming a second electrode layer 06 on the side of the first color organic light emitting layer 05 away from the driving substrate;

specifically, the second electrode layer 06 can be formed by a sputtering process, and due to the characteristic of good film-forming coating property of the sputtering process, the second electrode layer 06 covers the whole isolation column 04, so that the organic light-emitting layer can be encapsulated, impurities such as water and oxygen are prevented from invading the organic light-emitting layer, and the encapsulation effect of the display substrate is ensured. Specifically, the second electrode layer 06 may employ a transparent conductive oxide including, but not limited to, ITZO, IZO, ITO, and the like.

Step 3, as shown in fig. 6, forming a photoresist 07 on the driving substrate on which the second electrode layer 06 is formed, and exposing the photoresist 07 by using a mask 08;

the mask plate 08 includes a light-transmitting pattern and a light-blocking pattern, where the light-blocking pattern corresponds to the first color pixel region, and the light-transmitting pattern corresponds to the second color pixel region and the third color pixel region.

Step 4, as shown in fig. 7, after exposure and development, the photoresist of the first color pixel region is retained, and the photoresist of the second color pixel region and the third color pixel region is removed;

step 5, as shown in fig. 8, etching the first color organic light emitting layer 05 and the second electrode layer 06 in the second color pixel region and the third color pixel region, removing the first color organic light emitting layer 05 and the second electrode layer 06 in the second color pixel region and the third color pixel region, stripping the remaining photoresist, and retaining the first color organic light emitting layer 05 and the second electrode layer 06 in the first pixel region;

step 6, as shown in fig. 9, forming the second color organic light emitting layer 09 on the driving substrate after the step 5 by evaporation or deposition, where the second color organic light emitting layer 09 is broken at the side surface of the isolation pillar 04 due to the notch formed at the side surface of the isolation pillar 04; forming a second electrode layer 06 on the side of the second color organic light emitting layer 09 away from the driving substrate;

And 7, as shown in fig. 10, coating a photoresist 07 on the driving substrate subjected to the step 6, and exposing the photoresist 07 by using a mask plate 08, wherein the mask plate 08 comprises a light-transmitting pattern and a light-tight pattern, the light-tight pattern corresponds to the second color pixel region, and the light-transmitting pattern corresponds to the first color pixel region and the third color pixel region.

Step 8, as shown in fig. 11, after exposure and development, the photoresist of the second color pixel region is retained, and the photoresist of the first color pixel region and the third color pixel region is removed;

step 9, as shown in fig. 12, etching the second color organic light emitting layer 09 and the second electrode layer 06 in the first color pixel region and the third color pixel region, removing the second color organic light emitting layer 09 and the second electrode layer 06 in the first color pixel region and the third color pixel region, stripping the remaining photoresist, and retaining the second color organic light emitting layer 09 and the second electrode layer 06 in the second pixel region;

step 10, as shown in fig. 13, forming a third color organic light emitting layer 10 on the driving substrate after the step 9 by evaporation or deposition, where the third color organic light emitting layer 10 is broken at the side of the isolation pillars 04 due to the notches formed at the side of the isolation pillars 04; forming a second electrode layer 06 on the side of the organic light emitting layer 10 of the third color away from the driving substrate;

Step 11, as shown in fig. 14, a photoresist 07 is coated on the driving substrate after the step 10, and the photoresist 07 is exposed by using a mask plate 08, where the mask plate 08 includes a light-transmitting pattern and a light-impermeable pattern, the light-impermeable pattern corresponds to the third color pixel region, and the light-transmitting pattern corresponds to the first color pixel region and the second color pixel region.

Step 12, as shown in fig. 15, after exposure and development, the photoresist of the third color pixel region is retained, and the photoresist of the first color pixel region and the second color pixel region is removed;

step 13, as shown in fig. 16, etching the third color organic light emitting layer 10 and the second electrode layer 06 in the first color pixel region and the second color pixel region, removing the third color organic light emitting layer 10 and the second electrode layer 06 in the first color pixel region and the second color pixel region, stripping the remaining photoresist, and retaining the third color organic light emitting layer 10 and the second electrode layer 06 in the third pixel region.

The organic light emitting layers of different pixel regions can be prepared through the steps, and the organic light emitting layers of pixels with different colors are prepared by using a photolithography process instead of an FMM technology, so that the manufacturing cost is reduced, and the high PPI of the display substrate can be realized.

Step 14, as shown in fig. 17, forms the encapsulation layer 11.

An encapsulation layer 11 covering the display substrate formed with the light emitting device is formed, the encapsulation layer 11 may include a first encapsulation layer, a second encapsulation layer, and a third encapsulation layer stacked in sequence, and the first encapsulation layer may be formed on the driving substrate by chemical vapor deposition, physical vapor deposition, coating, or the like. The first packaging layer can provide packaging and protection for the functional structure in the display area. The second encapsulation layer may planarize the first encapsulation layer, and the third encapsulation layer may form an outer layer encapsulation. The first and third encapsulation layers may use inorganic materials including, for example, silicon nitride, silicon oxide, silicon oxynitride, and the like, and the second encapsulation layer may use organic materials including, for example, polyimide (PI), epoxy resin, and the like. Therefore, the first packaging layer, the second packaging layer and the third packaging layer form a composite packaging layer 11, and the packaging layer 11 forms multiple protection for the functional structure of the display area, so that a better packaging effect is achieved.

In the method embodiments of the present disclosure, the sequence numbers of the steps are not used to limit the sequence of the steps, and for those skilled in the art, the sequence of the steps is also within the protection scope of the present disclosure without creative efforts.

It should be noted that, in this specification, each embodiment is described in a progressive manner, and the same and similar parts between the embodiments are referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments, since they are substantially similar to the product embodiments, the description is simple, and reference may be made to the partial description of the product embodiments for relevant points.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used only to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered within the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. A display substrate, comprising:

a drive substrate;

a first electrode on the driving substrate;

2. The display substrate according to claim 1, wherein at least one side surface of the spacer pillar is formed with a notch.

3. The display substrate of claim 1, wherein the spacers are metal spacers.

4. The display substrate according to claim 3, wherein the spacers include a first metal pattern and a second metal pattern stacked in a direction close to the driving substrate, and an orthogonal projection of the second metal pattern on the driving substrate is located within an orthogonal projection of the first metal pattern on the driving substrate.

5. The display substrate according to claim 4, wherein the spacers further comprise a third metal pattern on a side of the second metal pattern close to the driving substrate, and an orthogonal projection of the second metal pattern on the driving substrate is located within an orthogonal projection of the third metal pattern on the driving substrate.

6. The display substrate according to claim 1, wherein the second electrode is formed using a transparent conductive oxide.

7. The display substrate of claim 1, wherein the pixel definition layer defines a plurality of open regions, and wherein the minimum width of the open regions is no greater than 2um.

8. The display substrate according to claim 1, wherein the height of the spacers is 0.5um to 3um.

9. A display device comprising the display substrate according to any one of claims 1 to 8.

10. A method for manufacturing a display substrate is characterized by comprising the following steps:

forming a driving substrate;

forming a first electrode on the driving substrate;

11. The method of manufacturing a display substrate according to claim 10, wherein the forming the spacers comprises:

and forming the isolation column with at least one circle of notches on at least one side surface.

12. The method of manufacturing a display substrate according to claim 11, wherein the forming the spacers comprises:

forming a second metal material layer on the driving substrate on which the pixel defining layer is formed, and forming a first metal material layer on one side, far away from the driving substrate, of the second metal material layer;

13. The method of manufacturing a display substrate according to claim 11, wherein the forming the spacers comprises:

14. The method for manufacturing a display substrate according to claim 12 or 13, wherein the first etching is dry etching.

15. The method of claim 10, wherein the pixel defining layer defines a plurality of pixel regions including a first color pixel region, a second color pixel region, and a third color pixel region, and wherein forming the organic light emitting layer and the second electrode on the side of the spacers away from the driving substrate comprises:

patterning the first color organic light emitting layer and the second electrode layer by adopting a photoetching process, and reserving the first color organic light emitting layer and the second electrode layer which are positioned in the first color pixel area;

depositing a second color organic light-emitting layer and a second electrode layer on one side of the isolation column away from the driving substrate in sequence;

and patterning the third color organic light emitting layer and the second electrode layer by adopting a photoetching process, and reserving the third color organic light emitting layer and the second electrode layer which are positioned in a third color pixel area.