CN112271267B

CN112271267B - Display back plate, manufacturing method thereof and display device

Info

Publication number: CN112271267B
Application number: CN202011170021.XA
Authority: CN
Inventors: 任泓雨; 李旭伟; 李仁佑; 樊浩原
Original assignee: BOE Technology Group Co Ltd; Mianyang BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Mianyang BOE Optoelectronics Technology Co Ltd
Priority date: 2020-10-28
Filing date: 2020-10-28
Publication date: 2023-01-13
Anticipated expiration: 2040-10-28
Also published as: CN112271267A

Abstract

The invention provides a display back plate, a manufacturing method thereof and a display device. The display back plate comprises a substrate, wherein an insulating layer is arranged on one side of the substrate, the display back plate is divided into a pixel area, a partition area and a punching area, at least one annular isolation dam is arranged on one side, far away from the substrate, of the insulating layer in the partition area, a protective layer is further arranged between the substrate and the annular isolation dam in the partition area, the orthographic projection of the protective layer on the substrate is at least partially overlapped with the orthographic projection of the annular isolation dam on the substrate, and the protective layer is used for shielding at least one of laser or static electricity. When laser irradiates the display back plate, the film layer on the surface of the annular isolation dam is not easy to peel off to cause packaging failure; when electrostatic discharge occurs on the annular isolation dam, the film layer on the surface of the annular isolation dam is not easy to break down, so that the field effect transistor nearby the annular isolation dam is not easy to lose efficacy and dark spots occur during display, and the display backboard is high in yield and good in display effect when display is achieved.

Description

Display back plate, manufacturing method thereof and display device

Technical Field

The invention relates to the technical field of display, in particular to a display back plate, a manufacturing method thereof and a display device.

Background

At present, in the display field, the punching screen replaces special-shaped bang screens and water drop screens, and the AMOLED is a novel flexible display device with higher display proportion. However, in the related art perforated screen, when laser is irradiated onto the display backplane (for example, the flexible display backplane requires a laser lift-off process in its manufacturing process), the display backplane is very susceptible to package failure; in addition, when the display is realized, dark spots are easy to appear on the display picture, and the display effect is poor.

Thus, the related art of the existing display backplane still needs to be improved.

Disclosure of Invention

The present invention has been completed based on the following findings of the inventors:

after a great deal of intensive investigation and deep experimental verification, the inventor finds that in the related art, the reason why the display back panel is very easy to have packaging failure or display picture has dark spots during display is as follows: referring to fig. 1a and 1b, when the display back plate 10 is provided with an annular isolation dam 3 disposed around the perforated region C to prevent package failure, if the display back plate 10 receives laser irradiation (as indicated by an arrow in fig. 1 b), the energy of the laser is easily released above the annular isolation dam 3, which causes peeling of a film layer 4 (typically, a package structure, which will not be described in detail later) disposed on the surface of the annular isolation dam, thereby causing package failure; in addition, when the display back plate 10 is subjected to an electrostatic test, air discharge and contact discharge can also cause energy to be released at one point on the surface of the annular isolation dam 3, so that the film layer 4 on the surface of the annular isolation dam is broken or fractured, the field effect transistor nearby is failed, dark spots occur during display, and the display effect is poor.

Based on this, the present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, an object of the present invention is to provide a display back plate, which is less likely to peel off a film layer on a surface of an annular barrier when laser light is irradiated thereon, is less likely to cause breakdown of a film layer on a surface of the annular barrier when electrostatic discharge occurs on the annular barrier, is less likely to fail a field effect transistor near the annular barrier, is less likely to cause shading in display, has a high yield in display, or has a good display effect.

In one aspect of the invention, a display backplane is provided. According to an embodiment of the invention, the display back plate comprises a substrate, an insulating layer is arranged on one side of the substrate, the display back plate is divided into a pixel area, a partition area and a punching area, the partition area is arranged around the punching area, the pixel area is arranged around the partition area, at least one annular isolation dam is arranged on one side, away from the substrate, of the insulating layer in the partition area, the annular isolation dam is arranged around the punching area, a protective layer is further arranged between the substrate and the annular isolation dam in the partition area, an orthographic projection of the protective layer on the substrate is at least partially overlapped with an orthographic projection of the annular isolation dam on the substrate, and the protective layer is used for shielding at least one of laser or static electricity. When laser irradiates the display back plate, the film layer on the surface of the annular isolation dam is not easy to peel off to cause packaging failure; when electrostatic discharge occurs on the annular isolation dam, the film layer on the surface of the annular isolation dam is not easy to break down, so that the field effect transistor nearby the annular isolation dam is not easy to lose efficacy, dark spots occur during display, and the display back plate is high in yield and good in display effect when display is achieved.

According to the embodiment of the invention, the orthographic projection of the protective layer on the substrate covers the orthographic projection of the annular isolation dam on the substrate.

According to an embodiment of the present invention, a surface of the annular isolation dam remote from the substrate has a top wall and two side walls, the top wall has a first end near the pixel region and connected to one of the side walls, a second end near the perforated region and connected to the other of the side walls, and an intermediate portion located between the first end and the second end, an orthographic projection of the protective layer on the substrate covers an orthographic projection of the two side walls on the substrate, a partial orthographic projection of the intermediate portion on the substrate, an orthographic projection of the first end on the substrate, and an orthographic projection of the second end on the substrate, and a gap is provided between a portion of the annular isolation dam covering an orthographic projection of the intermediate portion on the substrate and a portion of the annular isolation dam covering an orthographic projection of the first end on the substrate and an orthographic projection of the second end on the substrate.

According to the embodiment of the invention, the display back plate satisfies any one of the following conditions: the protective layer is arranged between the substrate and the gate insulating layer of the display back plate; the protective layer is arranged between the gate insulating layer of the display back plate and the interlayer insulating layer of the display back plate; the protective layer is arranged between the interlayer insulating layer of the display back plate and the annular isolation dam.

According to an embodiment of the invention, the protective layer is a plurality of annular metal layers arranged one inside the other.

According to an embodiment of the invention, the annular metal layer satisfies at least one of the following conditions: the number of the annular metal layers D =2n +1, wherein n is the number of the annular isolation dams; the width of a gap between two adjacent annular metal layers is not less than 7 mu m; the material of the annular metal layer comprises at least one of molybdenum, silver or aluminum.

In another aspect of the invention, a method of making the display backplane described above is provided. According to an embodiment of the invention, the method comprises: forming a protective layer on one side of the substrate in the partition region; forming an insulating layer on one side of a substrate; and forming at least one annular isolation dam on one side of the protective layer far away from the substrate in the isolation area. The method is simple and convenient to operate, easy to realize and easy for industrial production, and the display back plate can be effectively manufactured.

According to an embodiment of the invention, the method further comprises: when the protective layer is formed in the partition area, the protective layer is also formed on one side of the substrate in the punching area; when at least one annular isolation dam is formed in the partition region, at least one annular isolation dam is also formed on the side, away from the substrate, of the protective layer in the perforated region; carrying out laser lift-off treatment on the substrate; and removing the perforated area.

According to the embodiment of the invention, the protective layer and the grid electrode of the thin film transistor in the pixel area of the display backboard are formed through the same mask.

In yet another aspect of the present invention, a display device is provided. According to an embodiment of the present invention, the display device includes the display back plate described above. The display device has high yield and good display effect when realizing display, has all the characteristics and advantages of the display back plate, and is not repeated.

Drawings

Fig. 1a shows a schematic plan view of a display back plate in the related art.

FIG. 1b is a schematic cross-sectional view of the display back plate of FIG. 1a along the line a-a.

Fig. 2 is a schematic cross-sectional view of a display backplane according to an embodiment of the present invention.

Fig. 3 is a schematic cross-sectional view of a display back plate according to another embodiment of the invention.

Fig. 4 is a schematic cross-sectional view of a display back plate according to another embodiment of the invention.

FIG. 5 is a schematic cross-sectional view of a display backplane according to yet another embodiment of the present invention.

FIG. 6 is a flow chart illustrating a method for fabricating a display backplane according to an embodiment of the present invention.

Fig. 7a, 7b and 7c are schematic flow charts showing a method for fabricating a display backplate according to another embodiment of the present invention.

FIG. 8 is a flow chart of a method for fabricating a display backplane according to another embodiment of the present invention.

Fig. 9a, 9b and 9c are schematic flow charts illustrating a method for fabricating a display backplate according to still another embodiment of the present invention.

Reference numerals:

10: display backplane 1, 100: substrate 2, 200: insulating layer 210: the gate insulating layer 220: interlayer insulating layers 3, 300: annular isolation dam 311: first end 312: second end 313: the middle portion 320: side wall 4:

film layer

500, 500a, 500b, 500c on the surface of the annular barrier dam: protective layer p: gap A: pixel region B blocking region C: perforating area

Detailed Description

The following describes in detail embodiments of the present invention. The following examples are illustrative only and are not to be construed as limiting the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications.

In one aspect of the invention, a display backplane is provided. According to an embodiment of the present invention, referring to fig. 2 and 3, the display backplane includes a substrate 100, an insulating layer 200 is disposed on one side of the substrate 100, the display backplane is divided into a pixel region a, a blocking region B and a perforated region C, the blocking region B is disposed around the perforated region C, the pixel region a is disposed around the blocking region B, at least one annular isolation dam 300 is disposed on one side of the insulating layer 200 away from the substrate 100 in the blocking region B, the annular isolation dam 300 is disposed around the perforated region C, a protective layer 500 is further disposed between the substrate 100 and the annular isolation dam 300 in the blocking region B, an orthographic projection of the protective layer 500 on the substrate 100 at least partially overlaps an orthographic projection of the annular isolation dam 300 on the substrate, and the protective layer 500 is used for shielding at least one of laser or static electricity. When laser irradiates the display back plate, the protective layer 500 is arranged, so that most energy of the laser can be absorbed or reflected, the laser can be well shielded, and a film layer on the surface of the annular isolation dam 300 is not easy to peel off to cause packaging failure; in addition, when static electricity is released on the annular isolation dam, the protective layer 500 can be uniformly dispersed on the annular isolation dam, so that energy release of the static electricity is prevented from being concentrated on one point of the annular isolation dam 300 to be released, a good shielding effect is achieved on the static electricity, the film layer 4 on the surface of the annular isolation dam 300 is not prone to being broken down, failure of field effect transistors nearby the film layer is not prone to being caused, dark spots occur during display, and the display backboard is high in yield and good in display effect when display is achieved.

According to the embodiment of the present invention, it should be noted that, in this document, the partition region B is exemplified to have two annular isolation dams 300, but those skilled in the art can understand that the number of the annular isolation dams 400 in the partition region B may be other numbers, and will not be described repeatedly herein; in addition, in the partition region B, when more than two annular isolation dams 300 are provided, the heights of the different annular isolation dams 300 are not particularly limited, and may be the same or different, and in some embodiments of the present invention, when two annular isolation dams 300 are provided in the partition region B, the height of the annular isolation dam near the perforation region C is higher than the height of the annular isolation dam 300 near the pixel region a, so that the packaging effect is better.

According to an embodiment of the present invention, a specific arrangement of the protective layer is not particularly limited as long as it can shield at least one of laser light or static electricity, and specifically, the protective layer may have the following arrangement:

further, according to an embodiment of the present invention, referring to fig. 3, an orthographic projection of the protective layer 500 on the substrate 100 may be overlaid on an orthographic projection of the annular isolation dam 300 on the substrate 100. The arrangement of the protective layer 500 is simple and easy to implement, and the protective layer 500 covers the entire annular isolation dam 300, so that the shielding effect of the annular isolation dam on laser or static electricity is better.

Further, according to the embodiment of the present invention, referring to fig. 4, the inventors conducted extensive and intensive investigations and experimental verification on the position where the laser causes peeling of the film layer 4 on the surface of the annular isolation dam 300, and found that, when the annular isolation dam 300 has, away from the surface of the substrate 100, a top wall (not shown) having a first end 311 adjacent to the pixel region a and connected to one of the side walls 320, a second end 312 adjacent to the perforated region C and connected to the other of the side walls 320, and an intermediate portion 313 located between the first end 311 and the second end 312, since the energy of the laser is easily released concentratedly directly above and at the corner of the annular isolation dam 300, the orthographic projection of the protective layer on the substrate 100 covers the orthographic projections of the two side walls 320 on the substrate 100, the partial orthographic projection of the intermediate portion 313 on the substrate 100, the orthographic projection of the first end 311 on the substrate 100 and the orthographic projection of the second end 312 on the substrate 100, and the orthographic projection of the annular isolation dam portion 313 on the substrate 100 has a gap between the first end 311 a and the second end portion 500C of the annular isolation dam 100. Therefore, by the arrangement of the protective layer 500, the stress caused by the formation of the protective layer in the display backplane can be reduced on the premise that the protective layer 500 can exert the maximum laser shielding or electrostatic shielding effect, and the display backplane is more suitable for flexible display.

According to the embodiment of the present invention, further, the specific arrangement position of the protective layer in the display backplane is also not particularly limited. For example, in some embodiments of the present invention, the protective layer 500 may be disposed between the substrate 100 and the gate insulating layer 210 of the display backplane (the schematic structural diagram refers to fig. 5); in other embodiments of the present invention, the protective layer may also be disposed between the gate insulating layer of the display backplane and the interlayer insulating layer of the display backplane (not shown in the figure); in still other embodiments of the present invention, the protection layer may be further disposed between the interlayer insulating layer of the display backplane and the annular isolation dam (not shown in the figure). Therefore, the protective layer is flexible in arrangement position and easy to realize, and a film layer on the surface of the annular isolation dam is further not easy to peel off to cause packaging failure; further, the film layer on the surface of the annular isolation dam is not easy to break down when static electricity is released on the annular isolation dam.

In a specific embodiment of the present invention, the protective layer may be a plurality of annular metal layers that are nested with each other, such as the protective layer 500a, the protective layer 500b, and the protective layer 500c in fig. 4, and when the protective layer is a plurality of annular metal layers that are nested with each other, stress variation caused by the protective layer being disposed in the display backplane may be better avoided, and at the same time, a film layer on the surface of the annular isolation dam may be further prevented from being peeled off to cause package failure; further, when electrostatic discharge occurs on the annular isolation dam, the film layer on the surface of the annular isolation dam is not prone to breakdown, and therefore the display backboard is high in yield and good in display effect when display is achieved.

According to the embodiment of the present invention, at least one of the protection layers 500, for example, the protection layer 500a, the protection layer 500b, and the protection layer 500c, may be made of the same material as the source-drain metal layer in the thin film transistor array layer; or may be the same material as the gate metal layer in the thin film transistor array layer.

For example, the material of the protection layer 500 may be at least one of titanium, aluminum, copper, and molybdenum; for example, it may be a single-layer structure or a multi-layer structure; for example, an alloy structure of the above-described metal materials may be used.

For example, the material of the protective layer 500 may be a Ti/Al/Ti stack, or a stack structure of Ti/Al/Ti and Cu.

For example, the material of the protection layer 500 may be a semiconductor material, such as low temperature polysilicon, or indium tin oxide (IGZO), amorphous silicon, or the like, or a semiconductor material made of a conductor, or a crystallized amorphous silicon material, or the like.

For example, the material of the protection layer 500 may be an inorganic layer, such as silicon nitride, silicon oxide, or a combination of one or more thereof.

Further, according to an embodiment of the present invention, the number D of the annular metal layers may be 2n +1, where n is the number of the annular isolation dams 300; for example, referring to fig. 4, when the number n of the annular isolation dams 300 is 2, the number D of the annular metal layers may be 5; in other embodiments of the present invention, when the number n of the annular isolation dams 300 is 3, the number D of the annular metal layers may be 7, so as to further reduce stress in the display backplane and better achieve the effect of shielding laser or static electricity.

According to an embodiment of the present invention, the protection layer 500 may extend to the edge of the perforated region, i.e., the laser-drilled edge, so that the protection is more uniform.

For example, the protection layer 500 may be a ring shape, and the ring-shaped protection layer extends to the edge of the hole region.

According to an embodiment of the present invention, the material of the annular isolation dam 300 may be an organic layer, such as polyimide.

According to an embodiment of the present invention, the annular isolation dam 300 may be a groove structure (not shown), for example, a groove structure formed by using a Ti/AlTi stacked metal.

According to an embodiment of the present invention, the annular isolation dam 300 may be provided in plurality, and a plurality of annular isolation dams 300 extend to the edge of the perforated area.

According to an embodiment of the present invention, further, referring to fig. 4, a width of a gap p between two adjacent ring-shaped metal layers is not less than 7 μm; in some specific embodiments of the present invention, the width of the gap p between two adjacent annular metal layers may be specifically 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, or 12 μm, and the like. Therefore, the stress in the display back plate can be further lowered, and the effect of shielding laser or static electricity can be better realized; meanwhile, the manufacturing process is simple and easy to manufacture.

According to an embodiment of the present invention, further, the material of the annular metal layer may include at least one of molybdenum, silver, or aluminum. Therefore, the material source is wide and easy to obtain, the cost is low, and the shielding effect on laser or static electricity can be better achieved.

According to the embodiments of the present invention, it can be understood that, in addition to the foregoing structures, a person skilled in the art can understand that the display backplane may also include structures of a display backplane conventional in the related art, such as an organic light emitting device, a pixel defining layer, a thin film transistor array layer, a light shielding layer, and the like, which are not described in detail herein; in addition, in the present invention, the arrangement manner of other structures may be the same as that of the structure in the conventional display backplane, and redundant description is not repeated here.

In another aspect of the invention, a method of making the display backplane described above is provided. According to an embodiment of the present invention, referring to fig. 6 and fig. 7a, fig. 7b, and fig. 7c, the method may specifically include the following steps (it should be noted that, the following steps are only described as an example of forming a protective layer first and forming an insulating layer, but a person skilled in the art may understand that, in the present invention, the process steps are not limited by the following description, for example, the process steps may also be formed by forming the insulating layer first and then forming the protective layer, and will not be repeated herein):

s100: in the blocking region, a protective layer 500 is formed on one side of the substrate 100 (see fig. 7a for a schematic structural diagram).

According to an embodiment of the present invention, it is understood that a specific process for forming the protection layer 500 on one side of the substrate 100 may be a process that is conventional in the related art, for example, when the material of the protection layer is a metal, the specific process may be a deposition process, an evaporation process, and the like, and process steps, conditions, and parameters of the process may be the same as those of the process that is conventional in the related art, and therefore, redundant description thereof is omitted. Therefore, the method is simple and convenient to operate, easy to realize and easy for industrial production.

According to an embodiment of the present invention, further, the protection layer 500 may be formed through the same mask as the gate electrode of the thin film transistor in the pixel region of the display backplane. Therefore, the method is simple and convenient to operate, easy to realize, free of increasing manufacturing procedures and easy for industrial production.

S200: an insulating layer 200 is formed on one side of the substrate 100 (see fig. 7b for a schematic structural diagram).

According to an embodiment of the present invention, it is understood that the specific process of forming the insulating layer 200 on one side of the substrate 100 may be a process that is conventional in the related art, for example, the specific forming process may be a deposition process, an evaporation process, and the like, and process steps, conditions, and parameters thereof may be the same as those of the process steps, conditions, and parameters that are conventional in the related art, and are not described in detail herein. Therefore, the method is simple and convenient to operate, easy to realize and easy for industrial production.

S300: at least one annular isolation dam 300 is formed in the isolation region on the side of the protective layer 500 away from the substrate 100 (see fig. 7c for a schematic structural diagram).

According to the embodiment of the present invention, it can be understood that a specific process for forming at least one annular isolation dam 300 on a side of the protection layer 500 away from the substrate 100 in the isolation region may be a process conventional in the related art, and process steps, conditions, and parameters thereof may be the same as those of the process steps, conditions, and parameters conventional in the related art, and are not described in detail herein. Therefore, the method is simple and convenient to operate, easy to realize and easy for industrial production.

In further embodiments of the present invention, referring to fig. 8 and 9a, 9b, 9c, the method may further comprise the steps of:

s100': in the blocking area B and the punching area C, a protective layer 500 is formed on one side of the substrate 100, that is: when the protective layer 500 is formed in the blocking region B, the protective layer 500 is also formed on one side of the substrate in the hole-punching region C (see fig. 9a for a schematic structural diagram).

S200: an insulating layer 200 is formed on one side of the substrate 100 (see fig. 9b for a schematic structural diagram).

And S300': in the blocking region B, at least one annular isolation dam 300 is formed on a side of the protective layer 500 away from the substrate 100, that is: when at least one annular isolation dam 300 is formed in the partition region B, at least one annular isolation dam 300 is also formed on the side of the protective layer 500 in the perforated region C away from the substrate 100 (see fig. 9C for a schematic structural diagram).

According to the embodiment of the present invention, in the steps S100', S200 and S300', the specific forming manners of the protection layer 500, the insulation layer 200 and the annular isolation dam 300 may be the same as those described above, and will not be described in detail herein. Therefore, the film layer in the punching area C is not easy to peel off or break down in the process of manufacturing the display back plate, and the packaging effect is good.

Still further, according to an embodiment of the present invention, it can be understood that, referring to fig. 8, the method may further include the steps of:

s400: the substrate 100 is subjected to laser lift-off processing.

According to an embodiment of the present invention, a specific process for performing the laser lift-off treatment on the substrate 100 may be a conventional process in the related art, and process steps, conditions and parameters thereof may be the same as those of the conventional process in the related art, and are not described in detail herein. Therefore, the display back plate is simple and convenient to operate, easy to realize and easy to realize in industrial production, and can realize flexible display.

S500: and removing the perforated area C.

According to the embodiment of the present invention, the specific process for removing the punching region C may be a conventional process in the related art, and the process steps, conditions, and parameters may be the same as those of the conventional process in the related art, and will not be described herein again. Therefore, the method is simple and convenient to operate, easy to realize and easy for industrial production.

According to the embodiments of the present invention, it can be understood that, in the method for manufacturing the display back panel, in addition to the aforementioned steps, a person skilled in the art can understand that other step structures of a conventional method for manufacturing a display back panel in the related art may also be included, for example, forming an organic light emitting element, forming a pixel defining layer, forming a thin film transistor array layer, forming a light shielding layer, and the like, which are not described in detail herein; in addition, in the present invention, the specific implementation manner, process steps, conditions, and parameters of other steps may be the same as those in the conventional method for manufacturing a display backplane, and therefore, the detailed description thereof is omitted.

According to the embodiment of the present invention, the display device may further include other necessary structures and components besides the display back plate described above, and those skilled in the art may supplement and design the display device according to the specific kind and use requirements of the display device, and thus redundant description is not repeated herein.

According to the embodiment of the present invention, the specific kind of the display device is not particularly limited, and includes, for example, but is not limited to, a mobile phone, a tablet computer, a wearable device, a game machine, a television, or a vehicle-mounted display.

In the description of the present invention, it is to be understood that the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to imply that the number of technical features indicated are in fact significant. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A display back plate comprises a substrate, wherein an insulating layer is arranged on one side of the substrate, the display back plate is divided into a pixel area, a partition area and a punching area, the partition area is arranged around the punching area, and the pixel area is arranged around the partition area, and the display back plate is characterized in that at least one annular isolation dam is arranged on one side, far away from the substrate, of the insulating layer in the partition area and arranged around the punching area,

in the partition area, a protective layer is further arranged between the substrate and the annular isolation dam, the orthographic projection of the protective layer on the substrate is at least partially overlapped with the orthographic projection of the annular isolation dam on the substrate, and the protective layer is used for shielding at least one of laser or static electricity;

the surface of the annular isolation dam away from the substrate has a top wall and two side walls, the top wall has a first end near the pixel region and connected to one of the side walls, a second end near the perforated region and connected to the other of the side walls, and an intermediate portion between the first end and the second end, an orthographic projection of the protective layer on the substrate covers an orthographic projection of the two side walls on the substrate, a partial orthographic projection of the intermediate portion on the substrate, an orthographic projection of the first end on the substrate, and an orthographic projection of the second end on the substrate, and a gap is provided between the protective layer covering the partial orthographic projection of the intermediate portion on the substrate and the protective layer covering the orthographic projection of the first end on the substrate and the orthographic projection of the second end on the substrate.

2. A display backplane according to claim 1, wherein any of the following is satisfied:

the protective layer is arranged between the substrate and the gate insulating layer of the display back plate;

the protective layer is arranged between the gate insulating layer of the display back plate and the interlayer insulating layer of the display back plate;

the protective layer is arranged between the interlayer insulating layer of the display back plate and the annular isolation dam.

3. The display backplane of claim 1, wherein the protective layer is a plurality of annular metal layers disposed one inside the other.

4. The display backplane of claim 3, wherein the annular metal layer satisfies at least one of the following conditions:

the number of annular metal layers D =2n +1, wherein n is the number of annular isolation dams;

the width of a gap between two adjacent annular metal layers is not less than 7 mu m;

the material of the annular metal layer comprises at least one of molybdenum, silver or aluminum.

5. A method of making the display backsheet of any one of claims 1 to 4, comprising:

forming a protective layer on one side of the substrate in the partition region;

forming an insulating layer on one side of a substrate;

and forming at least one annular isolation dam on one side of the protective layer far away from the substrate in the isolation area.

6. The method of claim 5, further comprising:

when the protective layer is formed in the partition area, the protective layer is also formed on one side of the substrate in the punching area;

when at least one annular isolation dam is formed in the partition area, at least one annular isolation dam is also formed on the side, away from the substrate, of the protective layer in the perforated area;

carrying out laser lift-off treatment on the substrate;

and removing the perforated area.

7. The method of claim 5, wherein the protective layer and the gate electrode of the thin film transistor in the pixel region of the display backplane are formed by the same mask.

8. A display device comprising the display back sheet according to any one of claims 1 to 4.