CN110634937B

CN110634937B - Display substrate, preparation method thereof and display device

Info

Publication number: CN110634937B
Application number: CN201911053010.0A
Authority: CN
Inventors: 宋尊庆; 陈登云
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2022-04-26
Anticipated expiration: 2039-10-31
Also published as: CN110634937A

Abstract

The invention provides a display substrate, a preparation method thereof and a display device. The display substrate comprises a substrate, wherein a plurality of island regions, a hole region and a bridge region are arranged on the substrate, the island regions are separated from one another, the hole region is arranged between the adjacent island regions, the bridge region is connected with the adjacent island regions, the island regions comprise two deformation regions respectively connected with the bridge region, and a light-emitting region is arranged between the two deformation regions, the light-emitting region is used for displaying images, and the hole region and the deformation regions are used for forming holes which are used for transmitting light rays when the display substrate is stretched. The invention adopts the layout of the island region, the bridge region and the hole region, each island region comprises a light-emitting region for image display and deformation regions positioned at two sides of the light-emitting region, and the hole region and the deformation regions are used for forming holes during stretching, so that ambient light directly passes through the holes, the transparent display effect is realized, and the problems of lower resolution ratio and the like of the existing transparent display device are effectively solved.

Description

Display substrate, preparation method thereof and display device

Technical Field

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

Background

An Organic Light Emitting Diode (OLED) is an active Light Emitting display device, and has the advantages of self-luminescence, wide viewing angle, high contrast, low power consumption, wide color gamut, Light weight, thinness, and special shape. With the continuous development of display technology, OLED technology is increasingly applied to flexible displays and transparent displays. Transparent display is an important branch of display technology, and means that an image is displayed in a transparent state, so that a viewer can see not only an image in a display device but also a scene behind the display device, and Virtual Reality/Augmented Reality (VR/AR) and 3D display functions can be realized.

At present, in a transparent display device adopting the OLED technology, each display unit is divided into a light-emitting area and a transparent area, a pixel driving circuit and a light-emitting structure provided in the light-emitting area are used for image display, and the transparent area occupying a larger area proportion of the display unit is used for transmitting light. However, practical use shows that the transparent display device with such a structure has problems such as low resolution.

Disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a display substrate, a manufacturing method thereof, and a display device, so as to solve the problems of low resolution and the like of the existing transparent display device.

In order to solve the above technical problem, an embodiment of the present invention provides a display substrate, including a substrate, on which a plurality of island regions spaced apart from each other, a hole region disposed between adjacent island regions, and a bridge region connecting adjacent island regions are disposed, the island regions including two deformation regions respectively connected to the bridge region and a light emitting region disposed between the two deformation regions, the light emitting region being used for image display, and the hole region and the deformation regions being used for forming a hole through which light passes when stretched.

Optionally, the pore region comprises a plurality of micro-grooves or micro-pores penetrating through the substrate, providing deformation space and forming the pores when stretched; the deformation area comprises a deformation structure layer and an organic insulating layer which are overlapped on the substrate, and the deformation area is warped to form the hole when the deformation area is stretched.

Optionally, the deformation structure layer includes a plurality of pillars wrapping the connection line, a groove is formed between the pillars, and the organic insulating layer covers the pillars and the groove.

Optionally, the pillar includes a first insulating layer disposed on the substrate, a connection line disposed on the first insulating layer, and a second insulating layer disposed on the first insulating layer and wrapping the connection line; the grooves between the pillars expose the substrate.

Optionally, the light emitting region includes a driving structure layer and a light emitting structure layer stacked on the substrate; the connecting wire and the grid line or the data line in the light-emitting structure layer are arranged on the same layer and are made of the same material, and the organic insulating layer and the pixel defining layer in the light-emitting structure layer are arranged on the same layer and are made of the same material.

Optionally, the island region includes a first diagonal line in a direction in which the island region meets the bridge region, and a second diagonal line in mirror symmetry with the first diagonal line, the light-emitting region is in a strip shape extending along the second diagonal line, and the deformation region is in a block shape disposed on both sides of the light-emitting region.

Optionally, the light-emitting region includes a plurality of light-emitting units, and the plurality of light-emitting units are sequentially arranged along the second diagonal direction.

The embodiment of the invention also provides a display device which comprises the display substrate.

In order to solve the above technical problem, an embodiment of the present invention further provides a method for manufacturing a display substrate, including:

a plurality of island regions, a hole region and a bridge region are formed on a substrate, wherein the island regions are separated from each other, the hole region is arranged between the adjacent island regions, the bridge region is connected with the adjacent island regions, the island regions are formed to comprise two deformation regions respectively connected with the bridge region, the light emitting region is located between the two deformation regions and is used for displaying images, and the hole region and the deformation regions are used for forming holes which are used for transmitting light when being stretched.

Optionally, forming an island region on the substrate comprises:

forming a driving structure layer and a deformation structure layer on a substrate, wherein the driving structure layer is formed in the light-emitting area, the deformation structure layer is formed in the deformation area, the deformation structure layer comprises a plurality of columns wrapping the connecting lines, and grooves are formed among the columns;

and forming a light-emitting structure layer and an organic insulating layer, wherein the light-emitting structure layer is formed in the light-emitting area, the organic insulating layer is formed in the deformation area, and the organic insulating layer covers the cylinder and the groove.

Optionally, forming the driving structure layer and the deformation structure layer on the substrate includes:

forming an active layer on a substrate, the active layer being formed on the light emitting region;

forming a first insulating layer covering a substrate, and a gate electrode and a plurality of connection lines provided on the first insulating layer, the gate electrode being formed in the light-emitting region, the plurality of connection lines being formed in the deformation region;

forming a second insulating layer and a third insulating layer which cover the whole substrate, forming a first via hole which exposes the active layer in the light-emitting region, forming a plurality of columns which wrap the connecting line in the deformation region, and etching the third insulating layer, the second insulating layer and the first insulating layer among the columns to form the groove which exposes the substrate;

and forming a source electrode and a drain electrode on the third insulating layer, wherein the source electrode and the drain electrode are formed in the light-emitting region and are respectively connected with the active layer through the first via holes.

Optionally, forming the light emitting structure layer and the organic insulating layer includes:

forming a fourth insulating layer covering the source electrode and the drain electrode, wherein the fourth insulating layer is formed in the light-emitting area and is provided with a second through hole exposing the drain electrode;

forming an anode on the fourth insulating layer, wherein the anode is formed in the light-emitting region and connected to a drain electrode through a second via hole;

and forming a pixel defining layer covering the whole substrate, wherein the first pixel defining layer positioned in the light-emitting region is formed with an opening region exposing the anode, and the second pixel defining layer positioned in the deformation region is used as an organic insulating layer to cover the column and the groove.

The embodiment of the invention provides a display substrate, a preparation method thereof and a display device, wherein the display substrate adopts the layout of island regions, bridge regions and hole regions, each island region comprises a light-emitting region and two deformation regions, the two deformation regions are respectively connected with the bridge region, the light-emitting region is positioned between the two deformation regions, the light-emitting region is used for displaying images, and the hole regions and the deformation regions are used for forming holes during stretching, so that ambient light directly passes through the holes, the transparent display effect is realized, and the problems of low resolution and the like of the existing transparent display device are effectively solved.

Of course, not all of the advantages described above need to be achieved at the same time in the practice of any one product or method of the invention. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the embodiments of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention. The shapes and sizes of the various elements in the drawings are not to scale and are merely intended to illustrate the invention.

FIG. 1 is a schematic view of a display substrate according to an embodiment of the present invention;

FIG. 2 is a schematic diagram showing the structure of an island region, a hole region and a bridge region in a substrate according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating an active layer pattern formed according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a gate electrode and a connecting line pattern formed according to an embodiment of the present invention;

FIG. 5 is a schematic diagram illustrating a capacitor electrode pattern formed according to an embodiment of the present invention;

FIG. 6 is a schematic view illustrating a third insulating layer pattern according to an embodiment of the present invention;

FIG. 7 is a schematic representation of an embodiment of the present invention after source and drain electrode patterning;

FIG. 8 is a schematic view illustrating a fourth insulation layer pattern according to an embodiment of the present invention;

FIG. 9 is a schematic view of an anode pattern formed according to an embodiment of the present invention;

FIG. 10 is a schematic view of a pixel defining layer pattern formed according to an embodiment of the present invention;

FIG. 11 is a schematic view of an organic light emitting layer and a cathode pattern formed according to an embodiment of the present invention;

FIG. 12 is a schematic diagram illustrating an example of a patterned packaging layer according to an embodiment of the present invention;

FIG. 13 is a schematic view of a display substrate after forming an embodiment of the invention;

FIG. 14 is a schematic diagram illustrating the stress applied when the substrate is stretched according to the embodiment of the invention;

FIG. 15 is a schematic diagram illustrating a stretched structure of a substrate according to an embodiment of the invention.

Description of reference numerals:

1-a glass carrier plate; 10-a substrate; 11-a barrier layer;

12 — a first insulating layer; 13 — a second insulating layer; 14 — a third insulating layer;

15-a fourth insulating layer; 21-an active layer; 22 — a first gate electrode;

23 — a second gate electrode; 24-connecting lines; 25-a capacitive electrode;

26-source electrode; 27-a drain electrode; 31-an anode;

32 — a first pixel definition layer; 33 — a second pixel definition layer; 34 — an organic light emitting layer;

35-a cathode; 36-an encapsulation layer; 100-an island region;

200-bridge region; 300-hole area; 101-middle zone;

102 — border region.

Detailed Description

The following detailed description of embodiments of the invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The research of the inventor of the application finds that the existing transparent display device has the problems of low resolution ratio and the like, and is caused by the fact that the area of the transparent area is large. Generally, to achieve a better transparent display effect, the light transmittance of the display device needs to be more than 90%. With the existing structure in which each display unit is divided into a display region and a transparent region, it is necessary to design the transparent region area to be more than nine times the display region area. According to the existing manufacturing technology, the size of the pixel driving circuit in the display area reaches the technological limit, and the occupied area is difficult to further reduce. Since the area of the transparent region is determined by the area of the display region, the area of the display unit is large, the resolution is low, and the realization of high resolution is not facilitated (Pixels Per inc, PPI).

In order to solve the problems of low resolution and the like of the conventional transparent display device, the embodiment of the invention provides a display substrate. The main body structure of the display substrate comprises a substrate, wherein a plurality of island regions, a hole region and a bridge region are arranged on the substrate, the island regions are separated from one another, the hole region is arranged between every two adjacent island regions, the bridge region is connected with the adjacent island regions, the island regions comprise two deformation regions respectively connected with the bridge region, and a light-emitting region is arranged between the two deformation regions, the light-emitting region is used for displaying images, and the hole region and the deformation regions are used for forming holes which transmit light rays when the display substrate is stretched.

The embodiment of the invention provides a stretchable and transparent OLED display substrate, which adopts the layout of an island region, a bridge region and a hole region, wherein each island region comprises a light-emitting region and two deformation regions, the two deformation regions are respectively connected with the bridge region, the light-emitting region is positioned between the two deformation regions, the light-emitting region is used for displaying images, and the hole region and the deformation regions are used for forming holes during stretching, so that ambient light directly passes through the holes, the transparent display effect is realized, and the problems of lower resolution ratio and the like of the conventional transparent display device are effectively solved.

Fig. 1 is a schematic structural diagram of a display substrate according to an embodiment of the invention. As shown in fig. 1, the planar structure of the display substrate includes a plurality of islands 100 distributed in an array and spaced apart from each other, hole regions 300 between adjacent islands 100, and bridge regions 200 connecting adjacent islands 100 to each other, the islands 100 being used for image display, the hole regions 300 being used for providing deformation space when stretched and forming holes for transmitting light, and the bridge regions 200 being used for routing and transmitting pulling force. Each island 100 may include one or more pixel units, and each pixel unit includes 3 (e.g., red, green, blue) or 4 (e.g., red, green, blue, white) light emitting units emitting light of different colors. Each island 100 may be rectangular or square in a plane parallel to the substrate. The hole area 300 at the periphery of each island area is composed of a plurality of micro-grooves or micro-holes penetrating through the substrate, the micro-grooves or micro-holes are L-shaped or are in a shape of connecting a plurality of L-shapes, such as I-shaped, T-shaped and the like, and the width of the micro-grooves is 10-500 mu m. The bridge region 200 is located between the island region 100 and the hole region 300, or located between adjacent hole regions 300, and is connected to the adjacent island region 100, the bridge region 200 is L-shaped, or a shape formed by connecting a plurality of L-shapes, such as L-shaped ┙ shape, T-shaped, etc., the width of the bridge region 200 is 10 μm to 500 μm, and the embodiment is not limited.

In a plane perpendicular to the substrate, each light emitting unit includes a driving structure layer and a light emitting structure layer stacked on the substrate, the driving structure layer mainly includes a pixel driving circuit composed of a plurality of Thin Film Transistors (TFTs), and the light emitting structure layer mainly includes an anode, an organic light emitting layer, and a cathode. Each bridge region mainly comprises a connecting line and a structural layer covering the connecting line, the connecting line is used for realizing signal communication between adjacent island regions, the structural layer is used for transmitting pulling force, and the signal communication between the adjacent island regions is the signal communication between a light-emitting unit in one island region and a light-emitting unit in the other adjacent island region. For example, the connection line may connect the gate lines in the adjacent island regions, and may also connect the data lines in the adjacent island regions. Each hole area comprises a plurality of micro grooves or micro holes, the structural film layer and the substrate in each micro groove or micro hole are removed for providing deformation space during stretching, and the plurality of holes realize direct light passing through, so that the transparent display structure with certain stretchability of the embodiment of the invention is realized.

Fig. 2 is a schematic structural diagram showing an island region, a hole region and a bridge region in a substrate according to an embodiment of the present invention, wherein one island region includes one pixel unit (i.e., three light emitting units). As shown in fig. 2, the rectangular or square island 100 includes a first diagonal line facing the direction in which the island meets the bridge and a second diagonal line mirror-symmetrical to the first diagonal line, along the first diagonal line, the island 100 is divided into three regions, a middle region 101 on the second diagonal line, and side regions 102 respectively located on both sides of the middle region 101, the middle region 101 is in the shape of a rectangular or polygonal bar, and the side regions 102 are in the shape of a triangular or polygonal block. In the present embodiment, the middle region 101 is a light-emitting region and has a strip shape extending along the second diagonal line, and the border region 102 is a deformed region 102 and has a block shape disposed on both sides of the light-emitting region. The light emitting region comprises a plurality of light emitting units, the light emitting units are sequentially arranged along a second diagonal direction, and each light emitting unit comprises a driving structure layer and a light emitting structure layer which are stacked on the substrate. The deformation region comprises a deformation structure layer and an organic insulating layer, wherein the deformation structure layer and the organic insulating layer are stacked on the substrate, the deformation structure layer comprises a plurality of columns arranged at intervals on the substrate, each column is wrapped with a connecting line, a groove is formed between every two adjacent columns, and the organic insulating layer covers the columns and fills the grooves. Specifically, the deformation structure layer comprises a plurality of first insulating layers made of inorganic materials, the first insulating layers are arranged on the substrate at intervals, the connecting lines are arranged on the first insulating layers, the second insulating layers made of the inorganic materials are arranged on the first insulating layers and wrap the connecting lines, and the first insulating layers and the second insulating layers between the columns are etched to form grooves exposing the substrate. Since the first insulating layer and the second insulating layer of the inorganic material in each groove of the deformation region are removed, the rigidity of the deformation region is lower than that of the light-emitting region, that is, the deformation region is softer than the light-emitting region and is more easily deformed. Therefore, two sides of the light-emitting area are respectively connected with one side of the deformation area, the other sides of the two deformation areas are connected with the bridge area, when the display substrate is subjected to tensile force, the tensile force is transmitted to the deformation area from the bridge area, the deformation area connected with the bridge area is warped upwards or downwards, and holes for transmitting light rays are formed on two sides of the light-emitting area.

The technical solution of this embodiment is further described below through the preparation process of the array substrate of this embodiment, wherein the schematic structural diagrams are all cross-sectional views along a-a in fig. 2. The "patterning process" in this embodiment includes processes of depositing a film, coating a photoresist, exposing a mask, developing, etching, and stripping the photoresist, and is a well-established manufacturing process in the related art. The "photolithography process" referred to in this embodiment includes coating film coating, mask exposure, and development, and is a well-established production process in the related art. The deposition may be performed by a known process such as sputtering, evaporation, chemical vapor deposition, etc., the coating may be performed by a known coating process, and the etching may be performed by a known method, which is not particularly limited herein. In the description of the present embodiment, it is to be understood that "thin film" refers to a layer of a material deposited or coated on a substrate. The "thin film" may also be referred to as a "layer" if it does not require a patterning process or a photolithography process throughout the fabrication process. If a patterning process or a photolithography process is required for the "thin film" in the entire manufacturing process, the "thin film" is referred to as a "thin film" before the patterning process, and the "layer" after the patterning process. The "layer" after the patterning process or the photolithography process includes at least one "pattern".

The display substrate preparation process of this embodiment includes:

(1) and coating a flexible material on the glass carrier plate 1, and curing to form a film to form the substrate 10. In the embodiment of the invention, the substrate 10 is a flexible substrate and has a thickness of 5 μm to 30 μm. The flexible material can be polyimide PI, polyethylene terephthalate PET or polymer soft film with surface treatment.

(2) A Barrier film is deposited on the substrate 10 to form a Barrier (Barrier) layer 11 pattern. The barrier film may be made of silicon nitride SiNx, silicon oxide SiOx, or the like, and may be an inorganic material, a single layer, or a multilayer structure of silicon nitride/silicon oxide. In this embodiment, the barrier layer 11 is used to improve the water and oxygen resistance of the substrate 10. An active layer film is then deposited and patterned through a patterning process to form a pattern of an active layer 21 disposed on the barrier layer 11 in the light emitting region of the island region, as shown in fig. 3. In the patterning process for patterning the active layer film, the active layer film and the barrier layer of the deformation region, the bridge region, and the hole region of the island region are etched away to expose the surface of the substrate 10. In practical implementation, the barrier layers of the deformation region and the bridge region may also be thinned, that is, by etching to a smaller corresponding thickness, or may be subjected to opening patterning, that is, by etching to form a plurality of openings. Etching away the barrier layer of the deformation region and the bridge region, thinning treatment or opening patterning treatment are all used for reducing the rigidity of the deformation region and the bridge region so as to facilitate stretching of the bridge region and warping of the deformation region.

(3) A first insulating film and a first metal film are sequentially deposited and patterned through a patterning process to form a first insulating layer 12 covering the entire substrate 10 and a first gate electrode 22, a second gate electrode 23, a gate line (not shown) and a plurality of connection line 24 patterns disposed on the first insulating layer 12, the first gate electrode 22, the second gate electrode 23 and the gate line patterns being located in a light emitting region of an island region, and the plurality of connection line 24 patterns being located in a deformation region and a bridge region of the island region, respectively, as shown in fig. 4. The first insulating layer may be a single layer or a multilayer structure of silicon nitride/silicon oxide, such as silicon nitride SiNx or silicon oxide SiOx, and is also referred to as a gate insulating layer (GI). After this patterning process, the first insulating layer 12 remains in the hole region.

(4) A second insulating film and a second metal film are sequentially deposited, the second metal film is patterned through a patterning process, a second insulating layer 13 covering the first gate electrode 22, the second gate electrode 23, the gate line and the plurality of connecting lines 24 and a capacitor electrode 25 pattern arranged on the second insulating layer 13 are formed, the capacitor electrode 25 is located in a light-emitting region of the island region, the position of the capacitor electrode corresponds to the position of the second gate electrode 23, and the capacitor electrode 25 and the second gate electrode 23 form a capacitor, as shown in fig. 5. The second insulating layer may be a single layer or a multilayer structure of silicon nitride/silicon oxide, such as silicon nitride SiNx or silicon oxide SiOx, and is also referred to as a gate insulating layer (GI). After the composition process, the first insulating layer and the second insulating layer are reserved in the deformation area, the bridge area and the hole area of the island area.

(5) Depositing a third insulating film, patterning the third insulating film through a patterning process, forming a third insulating layer 14 pattern with two first via holes in the light emitting region of the island region, and etching away the third insulating layer 14, the second insulating layer 13, and the first insulating layer 12 in the two first via holes to expose the active layer 21, as shown in fig. 6. In the patterning process for patterning the third insulating film, the third insulating layer 14 of the deformation region of the island region is completely etched away, the second insulating layer 13 and the first insulating layer 12 between the connection lines 24 of the deformation region are etched away, and a plurality of grooves K are formed, and the plurality of grooves K expose the surface of the substrate 10; the third insulating layer 14, the second insulating layer 13 and the first insulating layer 12 are remained in the bridge region; the third insulating layer 14, the second insulating layer 13, the first insulating layer 12 and the substrate 10 at the location of the hole region are etched away. That is to say, a plurality of columns arranged at intervals are formed in the deformation area, and grooves are formed among the columns to form the deformation structure layer. Each column comprises a first insulating layer arranged on the substrate, a connecting wire arranged on the first insulating layer, and a second insulating layer arranged on the first insulating layer and wrapping the connecting wire. The first insulating layer and the second insulating layer of each groove are etched away to form a groove exposing the substrate. At the same time, the third insulating layer of the deformed region is completely removed. A first insulating layer disposed on the substrate, a plurality of connection lines disposed at intervals on the first insulating layer, a second insulating layer covering the plurality of connection lines, and a third insulating layer disposed on the second insulating layer are formed at the bridge region. In the pore region, all film layers including the substrate are etched away. The third insulating layer may be a single layer or a multilayer structure of silicon nitride/silicon oxide, such as silicon nitride SiNx or silicon oxide SiOx, and is also referred to as an interlayer Insulating Layer (ILD). In practical implementation, the third insulating layer in the bridge region may also be etched away or thinned.

It should be noted that, at the position where the connection line exists in the deformation region, a plurality of pillars wrapping the connection line and grooves between the pillars are formed, and at other positions where the connection line does not exist in the deformation region, the third insulating layer, the second insulating layer and the first insulating layer are all etched away to expose the surface of the substrate. In this way, the inorganic material layers (the first, second and third insulating layers) of the deformed region are mostly removed, so that the rigidity of the deformed region is less than that of the island region. Since the inorganic material layers of the bridge regions are all reserved, the rigidity of the deformation regions is also less than that of the bridge regions, so that the deformation regions are beneficial to warping when the display substrate is stretched.

(6) A third metal film is deposited and patterned through a patterning process, and a source electrode 26, a drain electrode 27, and a data line (not shown) pattern are formed in a light emitting region of the island region, and the source electrode 26 and the drain electrode 27 are connected to the active layer 21 through two first via holes, respectively, as shown in fig. 7. Thus, the active layer 21, the first gate electrode 22, the source electrode 26, and the drain electrode 27 constitute a driving thin film transistor T, the second gate electrode 23 and the capacitor electrode 25 constitute a storage capacitor C, and the driving thin film transistor T, the storage capacitor C, and other thin film transistors constitute a driving structure layer.

It should be noted that the light-emitting region of the island region and the bridge region at the periphery of the island region are both provided with connecting lines in two directions, the connecting line in one direction at least includes a gate connecting line, which is disposed on the same layer as the gate line and formed by the same patterning process, and the connecting line in the other direction at least includes a voltage connecting line and a data connecting line, which are disposed on the same layer as the data line and formed by the same patterning process.

(7) A fourth insulating film is coated on the substrate on which the patterns are formed, a fourth insulating layer 15 pattern covering the source electrode and the drain electrode is formed in the light emitting region of the island region through a mask exposure and development photolithography process, and a second via hole is formed in the fourth insulating layer 15 and exposes the drain electrode 27 of the driving thin film transistor T, as shown in fig. 8. Wherein the fourth insulating layer is also referred to as a Planarization Layer (PLN). In this photolithography process, the fourth insulating layer 15 is developed in the deformed region of the island region, the bridge region and the hole region, the plurality of groove structures are exposed in the deformed region of the island region, the third insulating layer 14 is exposed in the bridge region, and all the film layers including the substrate in the hole region are removed.

(8) A transparent conductive film is deposited on the substrate on which the aforementioned pattern is formed, the transparent conductive film is patterned through a patterning process, a pattern of an anode 31 is formed in a light emitting region of the island region, and the anode 31 is connected to the drain electrode 27 through a second via hole, as shown in fig. 9. The transparent conductive film may be Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO). After the patterning process, the deformed region of the island region exposes the plurality of groove structures, the bridge region exposes the third insulating layer 14, and all the film layers including the substrate at the hole region are removed.

(9) A Pixel defining film is coated on the substrate on which the aforementioned pattern is formed, a Pixel defining Layer (Pixel Define Layer) pattern is formed by a photolithography process, the Pixel defining Layer includes a first Pixel defining Layer 32 pattern located at a light emitting region of an island region and a second Pixel defining Layer 33 pattern located at a deformation region and a bridge region of the island region, i.e., the first Pixel defining Layer 32 pattern and the second Pixel defining Layer 33 pattern are formed by the same photolithography process using the same material, the first Pixel defining Layer 32 defines an opening region exposing the anode 31 at each light emitting cell, the second Pixel defining Layer 33 covers a plurality of pillars and grooves of the deformation region, and a third insulating Layer 14 covering the bridge region, and the Pixel defining film of the hole region is developed as shown in fig. 10. The pixel defining layer can be polyimide, acrylic or polyethylene terephthalate, and the like, and the second pixel defining layer covering the plurality of columns and the grooves in the deformation area is used as an organic insulating layer.

(10) An organic light emitting layer 34 and a cathode 35 are patterned in this order on the substrate on which the aforementioned patterns are formed. The organic light emitting layer 34 and the cathode 35 are formed in a light emitting region of the island region, the organic light emitting layer 34 is formed in an opening region defined by the first pixel defining layer 32 to be connected to the anode electrode 31, and the cathode 35 is disposed on the organic light emitting layer 34 and the first pixel defining layer 32, as shown in fig. 11. The organic light emitting layer 34 mainly includes an emission layer (EML). In practical implementation, the organic light emitting layer may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer sequentially arranged to improve efficiency of injecting electrons and holes into the light emitting layer, and the cathode may be made of one of metal materials such as magnesium Mg, silver Ag, aluminum Al, copper Cu, lithium Li, or an alloy of the above metals. The organic light-emitting layer and the cathode may be formed by vapor deposition, inkjet printing, or the like.

(11) An encapsulation film is applied over the substrate in the aforementioned pattern, covering the island and bridge regions, forming an encapsulation layer 36 pattern, as shown in fig. 12. In the process of coating the encapsulation film, because the step difference at the boundary between the bridge region and the hole region is larger, the encapsulation layer 36 is broken at the boundary between the bridge region and the hole region, and the encapsulation layer 36 at the hole region is formed on the glass carrier 1. The packaging film can be of an inorganic/organic laminated structure, such as an inorganic/organic/inorganic three-layer structure or an inorganic/organic/inorganic five-layer structure, the inorganic material can be silicon oxide, aluminum oxide, silicon nitride or silicon oxynitride, the organic material can be a flexible high polymer material based on PET, the packaging film has a good packaging effect, can effectively prevent water and oxygen from entering the organic light emitting layer, and has the characteristic of flexible deformation, so that the tensile deformation of the display substrate can be realized.

(12) Finally, the glass carrier 1 is peeled off, and the encapsulation layer 36 in the hole region is peeled off together with the glass carrier 1, thereby forming the stretchable and transparent display substrate according to the embodiment of the invention, as shown in fig. 13.

Fig. 14 is a schematic diagram of a stress when the display substrate is stretched according to the embodiment of the present invention, and fig. 15 is a schematic diagram of a structure after the display substrate is stretched according to the embodiment of the present invention, wherein the first direction is a pulling direction, and the second direction is a direction perpendicular to the pulling direction. As shown in fig. 14 and 15, each island region is divided into a light-emitting region and a deformation region, a light-emitting structure for image display is provided in the light-emitting region, connection lines for signal communication between adjacent island regions are provided in the deformation region, and a pixel drive circuit may be disposed in the light-emitting region and the deformation region. Before stretching, the hole area is used as a transparent area; after stretching, the deformed regions and the hole regions serve as transparent regions. Since most of the inorganic material layer of the deformation region is removed, the flexibility of the deformation region is greater than the flexibility of the island region and the bridge region, i.e., the rigidity of the deformation region is less than the rigidity of the island region and the bridge region. When the display substrate is subjected to a tensile force in a first direction, the tensile force simultaneously deforms the hole region and the bridge region. Wherein the width of the hole region extending along the second direction increases, the length of the hole region extending along the first direction increases, the length of the bridge region extending along the first direction increases, and the width of the bridge region extending along the second direction increases. Meanwhile, the bridge area transmits the tensile force to the deformation area, one side of the deformation area is adjacent to the hole area extending along the first direction and the bridge area extending along the second direction, the other side of the deformation area is adjacent to the hole area extending along the second direction, and the rigidity of the deformation area is smaller than that of the bridge area, so that the deformation area on one side of the island area is tilted upwards, the deformation area on the other side of the island area is tilted downwards, the deformation area is converted into a three-dimensional structure through warping deformation, and two holes are formed in the island area under the driving of the deformation of the hole area and the bridge area. Because the light-emitting area of the island area is arranged in the middle of the island area and between the two deformation areas, the pulling forces transmitted to the light-emitting area by the two deformation areas are equal in magnitude and opposite in direction, and meanwhile, the rigidity of the light-emitting area is greater than that of the deformation areas, the light-emitting area of the island area keeps an original posture, cannot deform or change position, and ensures normal light emission. Therefore, when the display substrate is subjected to tension, the stretched and expanded hole area is transparent, two holes generated by warping on two sides of the light-emitting area are also transparent, ambient light can directly penetrate through the hole area and the holes, and the area of the transparent area is effectively increased.

It can be seen from the structure of the display substrate and the above-mentioned manufacturing process of the embodiment of the present invention that the stretchable and transparent OLED display substrate provided by the embodiment of the present invention adopts the layout of the island regions, the bridge regions and the hole regions, each island region is provided with a light emitting region and a deformation region, the deformation region is used for warping and converting into a hole during stretching, and when the light emitting region displays an image, the hole region and the hole together form a transparent region through which ambient light directly passes, so that transparent display is achieved.

In the existing structure, in order to ensure the transparent display effect, the area of the transparent region needs to be determined according to the area of the light emitting region, so that the area of the display unit is large, the resolution ratio is low, and the transmittance of the transparent display is fixed. Compared with the prior art, the display substrate has the advantages that the deformation area and the holes are used as the transparent areas, the size of the holes can be adjusted through tensile force, and the warping degree of the deformation area can also be adjusted through the tensile force, so that the transmittance of the display substrate can be adjusted through the tensile force, and transparent display with adjustable transmittance is achieved. The display substrate of the embodiment of the invention can adjust the transmittance, so that the area of the transparent area is not required to be determined according to the area of the light-emitting area, the area of the pixel unit can be reduced, the resolution is effectively improved, the high-resolution display is favorably realized, and the defects of lower resolution and the like of the conventional transparent display device are effectively overcome. Meanwhile, since the warpage is only generated in the deformation region of the island region, and the light emitting region of the island region is kept unchanged, the influence of the stretching degree of the display substrate on the display resolution is small, and the requirements of VR, AR and 3D display fields can be met.

In the existing structure, some metal wires, inorganic material layers or colored organic material layers are still arranged in the transparent area, and the metal wires and the material layers have certain reflection and refraction effects on light, so that the transparency is influenced to a certain degree. Compared with the existing structure, the transparent area in the embodiment of the invention adopts the deformation area and the hole as the transparent area, although the deformation area is provided with the connecting line and the inorganic material layer, the deformation area is converted into the hole with the three-dimensional structure through warping, the ambient light can directly pass through the hole without being reflected or refracted by the connecting line and the inorganic material layer, and the hole area is not provided with the substrate and the structure layer, so that the transparent area in the embodiment of the invention can realize 100% transparency. Meanwhile, the holes are used as the transparent areas in the embodiment of the invention, so that the flexible substrate is not required to be limited to be transparent, the inorganic material layers and the organic material layers are not required to be limited to be transparent, and the flexible substrate, the inorganic material layers and the organic material layers are selected to have a wide range and strong adaptability.

Furthermore, the preparation process of the display substrate can be realized by utilizing the existing mature preparation equipment, the improvement on the existing process is small, the preparation process can be well compatible with the existing preparation process, and the preparation method has the advantages of simple process realization, high production efficiency, low production cost, high yield and the like, and has good application prospect.

It should be noted that the structure and the manufacturing process thereof shown in the embodiment of the present invention are only an exemplary illustration. In practical implementation, the corresponding structure can be changed and the patterning process can be increased or decreased according to actual needs. For example, not only the light emitting region of the island region can be used for placing the pixel driving circuit, but also the deformation region of the island region can be used for placing a part of the pixel driving circuit, and even the bridge region can be used for placing a part of the pixel driving circuit, and only the posts of the deformation region need to wrap the connecting wires and a part of the pixel driving circuit. Because part of the pixel driving circuits are arranged in the deformation area and the bridge area, the occupied area of the light-emitting area can be further reduced, the area of the transparent area is increased, and the realization of high resolution is facilitated. As another example, one island region may include only one sub-pixel, i.e., one light emitting unit. For another example, the display substrate may have a top-emission structure or a bottom-emission structure, the thin film transistor may have a top-gate structure or a bottom-gate structure or a single-gate structure or a double-gate structure, and the thin film transistor may be an amorphous silicon (a-Si) thin film transistor, a Low Temperature Polysilicon (LTPS) thin film transistor, or an Oxide (Oxide) thin film transistor. For another example, the hole region structure may be implemented by other preparation methods, including that when the third insulating film is patterned in step (5), the substrate is retained, after the encapsulation film is completed, the glass carrier is peeled off, the display substrate is turned over, and the substrate is etched at the hole region position from the side of the substrate away from the structural layer to form the opening. For another example, other electrodes, leads and structural film layers may be further disposed in the driving structure layer and the light emitting structure layer, and the invention is not limited herein.

On the basis of the technical concept of the display substrate, the embodiment of the invention also provides a preparation method of the display substrate. The preparation method of the display substrate comprises the following steps:

Wherein the pore region comprises a plurality of micro-grooves or micro-pores penetrating through the substrate, providing deformation space and forming the pores when stretched; the deformation area comprises a deformation structure layer and an organic insulating layer which are overlapped on the substrate, and the deformation area is warped to form the hole when the deformation area is stretched.

Wherein forming an island region on a substrate comprises:

Wherein, form drive structural layer and deformation structural layer on the basement, include:

Wherein, forming the light emitting structure layer and the organic insulating layer includes:

The island region comprises a first diagonal line and a second diagonal line, the first diagonal line faces the direction in which the island region and the bridge region are connected, the second diagonal line is in mirror symmetry with the first diagonal line, the light emitting region is in a strip shape extending along the second diagonal line, and the deformation region is in a block shape arranged on two sides of the light emitting region.

The light emitting region comprises a plurality of light emitting units, and the plurality of light emitting units are sequentially arranged along the second diagonal direction.

The detailed preparation process of the preparation method of the display substrate according to the embodiment of the present invention has been described in detail in the foregoing embodiments, and is not repeated herein.

The embodiment provides a preparation method of a display substrate, which adopts the layout of an island region, a bridge region and a hole region, wherein each island region comprises a light-emitting region and two deformation regions, the two deformation regions are respectively connected with the bridge region, the light-emitting region is positioned between the two deformation regions, the light-emitting region is used for image display, and the hole region and the deformation regions are used for forming holes during stretching, so that ambient light directly passes through the holes, the transparent display effect is realized, and the problems of low resolution and the like of the existing transparent display device are effectively solved. The preparation process of the display substrate provided by the embodiment of the invention can be realized by utilizing the existing mature preparation equipment, has small improvement on the existing process, can be well compatible with the existing preparation process, has the advantages of simple process realization, high production efficiency, low production cost, high yield and the like, and has good application prospect.

The embodiment of the invention also provides a display device which comprises the display substrate of the embodiment. The display device can be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like, and can also be a product or component with VR, AR and 3D display functions.

In the description of the embodiments of the present invention, it should be understood that the terms "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A display substrate is characterized by comprising a substrate, wherein a plurality of island regions, a hole region and a bridge region are arranged on the substrate, the island regions are separated from one another, the hole region is arranged between every two adjacent island regions, the bridge region is connected with the adjacent island regions, the island regions comprise two deformation regions respectively connected with the bridge region, and a light-emitting region is arranged between the two deformation regions, the light-emitting region is used for displaying images, and the hole region and the deformation regions are used for forming holes which are used for transmitting light rays when the substrate is stretched; the deformation region is in a block shape and is arranged on two sides of the light emitting region, the deformation region comprises a deformation structure layer and an organic insulating layer which are stacked on a substrate, the deformation structure layer comprises a plurality of columns which are arranged on the substrate at intervals, each column comprises a first insulating layer arranged on the substrate, a connecting line arranged on the first insulating layer and a second insulating layer which is arranged on the first insulating layer and wraps the connecting line, and the first insulating layer and the second insulating layer between the columns are etched to form a groove exposing the substrate.

2. The display substrate according to claim 1, wherein the hole region comprises a plurality of micro grooves or micro holes penetrating through the substrate, providing a deformation space and forming the hole when stretched, and the deformation region is warped to form the hole when stretched.

3. The display substrate of claim 2, wherein the organic insulating layer covers the pillars and the grooves.

4. The display substrate according to claim 3, wherein the light emitting region comprises a driving structure layer and a light emitting structure layer stacked on a substrate; the connecting wire and the grid line or the data line in the light-emitting structure layer are arranged on the same layer and are made of the same material, and the organic insulating layer and the pixel defining layer in the light-emitting structure layer are arranged on the same layer and are made of the same material.

5. The display substrate according to any one of claims 1 to 4, wherein the island region includes a first diagonal line extending in a direction in which the island region meets the bridge region, and a second diagonal line mirror-symmetrical to the first diagonal line, and the light-emitting region has a strip shape extending along the second diagonal line.

6. The display substrate according to claim 5, wherein the light-emitting region includes a plurality of light-emitting units, and the plurality of light-emitting units are sequentially arranged in the second diagonal direction.

7. A display device comprising the display substrate according to any one of claims 1 to 6.

8. A method for preparing a display substrate is characterized by comprising the following steps:

forming a plurality of island regions spaced apart from each other, a hole region disposed between adjacent island regions, and a bridge region connecting adjacent island regions on a substrate, the island regions being formed to include two deformed regions connected to the bridge region, respectively, and a light-emitting region disposed between the two deformed regions, the light-emitting region being used for image display, the hole region and the deformed regions being used to form a hole through which light passes when stretched; the deformation region is in a block shape and is arranged on two sides of the light emitting region, the deformation region comprises a deformation structure layer and an organic insulating layer which are stacked on a substrate, the deformation structure layer comprises a plurality of columns which are arranged on the substrate at intervals, each column comprises a first insulating layer arranged on the substrate, a connecting line arranged on the first insulating layer and a second insulating layer which is arranged on the first insulating layer and wraps the connecting line, and the first insulating layer and the second insulating layer between the columns are etched to form a groove exposing the substrate.

9. The method of claim 8, wherein forming an island region on a substrate comprises:

10. The method of claim 9, wherein forming the driving structure layer and the deforming structure layer on the substrate comprises:

11. A manufacturing method according to claim 10, wherein forming a light emitting structure layer and an organic insulating layer comprises:

12. The production method according to any one of claims 8 to 11, wherein the island region includes a first diagonal line in a direction in which the island region meets the bridge region, and a second diagonal line which is mirror-symmetrical to the first diagonal line, the light-emitting region has a strip shape extending along the second diagonal line, and the deformed region has a block shape provided on both sides of the light-emitting region.

13. The production method according to claim 12, wherein the light-emitting region includes a plurality of light-emitting units, which are arranged in order in the second diagonal direction.