CN113451346A

CN113451346A - Display substrate, manufacturing method thereof and transfer method of light-emitting element

Info

Publication number: CN113451346A
Application number: CN202010231078.XA
Authority: CN
Inventors: 陈右儒
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2020-03-27
Filing date: 2020-03-27
Publication date: 2021-09-28
Anticipated expiration: 2040-03-27
Also published as: CN113451346B

Abstract

A display substrate and a manufacturing method thereof, a transfer method of a light-emitting element, wherein the display substrate is used for binding the light-emitting element which is carried by a bearing substrate and is stripped from an original substrate; the display substrate includes: a plurality of pixel regions arranged in a matrix, the pixel regions including: a binding region and a non-binding region surrounding the binding region, each pixel region including: the driving back plate, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving back plate, is positioned in the non-binding area and is used for being connected with the driving back plate; the adhesion layer and the connection electrode are arranged on the same layer and are positioned in the binding region for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. The application can not only save time, but also save production cost.

Description

Display substrate, manufacturing method thereof and transfer method of light-emitting element

Technical Field

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

Background

Light Emitting Diode (LED) technology has been developed for nearly thirty years, and provides a solid foundation for its wider application from the original solid-state lighting power supply to the backlight source in the display field to the LED display screen. With the development of chip manufacturing and packaging technologies, sub-millimeter Light Emitting Diode (Mini LED) display of about 50 to 60 micrometers and Micro Light Emitting Diode (Micro LED) display of less than 15 micrometers gradually become a hot spot of display panels. The Micro LED display has the significant advantages of low power consumption, high color gamut, high stability, high resolution, ultra-thin property, easy realization of flexible display, and the like, and is expected to become a more excellent display technology for replacing Organic Light Emitting Diode (OLED) display.

One technical difficulty with Micro LED display technology is the bulk transfer technology. The Micro LED can only be prepared by epitaxial growth, and how to transfer the Micro LED from the initial epitaxial substrate onto the display substrate simply and reliably is a problem in the industry, which hinders the development of the Micro LED display and causes the slow development of the Micro LED display. The Micro LED transfer technology in the related art is time-consuming and high in production cost.

Content of application

The application provides a display substrate, a manufacturing method thereof and a transfer method of a light-emitting element, which can save time and reduce production cost.

In a first aspect, the present application provides a display substrate for binding light emitting elements peeled from an original substrate and carried by a carrier substrate; the display substrate includes: a plurality of pixel regions arranged in a matrix, the pixel regions including: a binding region and a non-binding region surrounding the binding region, each pixel region including: the driving back plate, the connecting electrode, the adhesion layer and the auxiliary electrode;

the connecting electrode is arranged on one side of the driving back plate, is positioned in a non-binding area and is used for being connected with the driving back plate; the adhesion layer and the connecting electrode are arranged on the same layer, are positioned in a binding region and are used for binding the light-emitting element; the auxiliary electrode is used for connecting the connecting electrode and the light-emitting element.

In one possible implementation, the driving back plate includes: a substrate, a thin film transistor, a power supply electrode and a flat layer;

the thin film transistor is arranged on one side of the substrate, the power supply electrode is arranged on one side of the thin film transistor, which is far away from the substrate, and the flat layer is positioned on one side of the power supply electrode, which is far away from the substrate; the power supply electrode is connected with a drain electrode of the thin film transistor;

wherein the length of the planarization layer along the direction perpendicular to the substrate is greater than 1.5 micrometers.

In one possible implementation manner, in each pixel region, a first via hole and a second via hole are arranged on the flat layer;

the power supply electrode includes: the first power supply electrode and the second power supply electrode are connected with the drain electrode of the thin film transistor; the connection electrode includes: the first connecting electrode and the second connecting electrode are respectively positioned on two sides of the binding region;

the first connecting electrode is electrically connected with the first power supply electrode through the first via hole, and the second connecting electrode is electrically connected with the second power supply electrode through the second via hole.

In one possible implementation, the light emitting element includes: a first electrode and a second electrode, the light emitting element including: a first surface and a second surface arranged oppositely; the first electrode and the second electrode are positioned on the second surface;

the adhesive layer is in direct contact with the first surface of the light-emitting element;

the viscosity of the adhesion layer is less than 500 millipascals per second, and the thickness of the adhesion layer is less than 100 nanometers.

In one possible implementation, in each pixel region, the auxiliary electrode includes: a first auxiliary electrode and a second auxiliary electrode;

the first auxiliary electrode is used for connecting the first electrode and the first connecting electrode, and the second auxiliary electrode is used for connecting the second electrode and the second connecting electrode.

In one possible implementation, the connection electrode and the auxiliary electrode are integrally formed.

In a second aspect, the present application further provides a method for manufacturing a display substrate, for manufacturing the display substrate, the method including:

forming a driving back plate;

forming a connection electrode on the driving back plate;

forming an insulating support layer which is positioned in a non-binding area and used for limiting a binding area on the driving back plate on which the connecting electrode is formed; an overlapping area exists between the orthographic projection of the insulating support layer on the driving back plate and the orthographic projection of the connecting electrode on the driving back plate;

forming an adhesion layer on the driving back plate with the insulating support layer by adopting a printing process;

aligning the bearing substrate and the driving back plate with the adhesive layer by using alignment equipment, so that the light-emitting element on the bearing substrate is adhered to the adhesive layer in the binding area;

heating the aligned bearing substrate and the driving backboard with the adhesive layer formed thereon to cure the adhesive layer so as to fix the light-emitting element;

sequentially stripping the bearing substrate and the insulating support layer to expose the connecting electrode;

forming an auxiliary electrode connecting the connection electrode and the light emitting element.

In one possible implementation, the forming a driving backplate includes:

providing a substrate;

forming a thin film transistor on the substrate;

forming a power supply electrode comprising a first power supply electrode and a second power supply electrode on one side of the thin film transistor far away from the substrate;

and forming a flat layer comprising a first via hole and a second via hole on one side of the power supply electrode far away from the thin film transistor.

In one possible implementation manner, the heating the aligned carrier substrate and the driving backplane with the adhesion layer formed thereon includes:

and heating the aligned bearing substrate and the original display substrate with the original adhesion layer, wherein the heating time is 25-35 minutes, and the heating temperature is 200-230 ℃.

In one possible implementation, the peeling the carrier substrate includes:

and stripping the bearing substrate by adopting a laser process and a physical stripping process.

In one possible implementation, the peel-off insulating support layer includes:

and stripping the insulating support layer by adopting a plasma etching process, wherein the etching time is 20-40 minutes.

In a third aspect, the present application also provides a method for transferring a light emitting element, the method comprising:

providing a bearing substrate;

attaching the bearing substrate to the original substrate, and irradiating one side of the original substrate, which is far away from the bearing substrate, by adopting a laser process so as to peel the light-emitting element from the original substrate;

the light-emitting element carried on the carrying substrate is transferred into the display substrate by adopting the manufacturing method of the display substrate.

The application provides a display substrate, a manufacturing method thereof and a transfer method of a light-emitting element, wherein the display substrate is used for binding the light-emitting element which is borne by a bearing substrate and is stripped from an original substrate; the display substrate includes: a plurality of pixel regions arranged in a matrix, the pixel regions including: a binding region and a non-binding region surrounding the binding region, each pixel region including: the driving back plate, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving back plate, is positioned in the non-binding area and is used for being connected with the driving back plate; the adhesion layer and the connection electrode are arranged on the same layer and are positioned in the binding region for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. This application is through bearing the weight of on the carrying substrate and setting up the binding region at display substrates from the light emitting component that original base plate was peeled off, through auxiliary electrode and connection electrode connection light emitting component and drive backplate, has reduced the counterpoint precision, has avoided using the counterpoint equipment of high accuracy, not only can save time, can save manufacturing cost moreover.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. Other advantages of the present application may be realized and attained by the instrumentalities and combinations particularly pointed out in the specification and the drawings.

Drawings

The accompanying drawings are included to provide an understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the examples serve to explain the principles of the disclosure and not to limit the disclosure.

Fig. 1 is a schematic structural diagram of a display substrate according to an embodiment of the present disclosure;

FIG. 2 is a top view of one pixel region of FIG. 1;

FIG. 3 is a schematic structural diagram of a carrier substrate according to an exemplary embodiment;

fig. 4 is a schematic structural view of a light-emitting element according to an exemplary embodiment;

FIG. 5 is a schematic diagram of a structure of a display substrate according to an exemplary embodiment;

fig. 6 is a flowchart of a method for manufacturing a display substrate according to an embodiment of the present disclosure;

fig. 7-15 are schematic diagrams illustrating a method of fabricating a display substrate according to an exemplary embodiment;

fig. 16 is a flowchart of a transfer method of a light emitting element according to an embodiment of the present application;

fig. 17 to 19 are schematic diagrams of a transfer method of a light emitting element according to an exemplary embodiment.

Detailed Description

The present application describes embodiments, but the description is illustrative rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are possible. Any feature or element of any embodiment may be used in combination with or instead of any other feature or element in any other embodiment, unless expressly limited otherwise.

The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique application as defined in the claims. Any feature or element of any embodiment may be combined with features or elements from other applications to form yet another unique application defined by the claims. Thus, it should be understood that any of the features shown and/or discussed in this application may be implemented alone or in any suitable combination. Accordingly, the embodiments are not limited except as by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

Further, in describing representative embodiments, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other orders of steps are possible as will be understood by those of ordinary skill in the art. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. Further, the claims directed to the method and/or process should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the embodiments of the present application.

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

Fig. 1 is a schematic structural diagram of a display substrate according to an embodiment of the present disclosure, and fig. 2 is a top view corresponding to a pixel region in fig. 1. As shown in fig. 1 and fig. 2, the display substrate provided in the embodiment of the present application is used for binding the light emitting elements 50 peeled from the original substrate and carried by the carrier substrate. The display substrate includes: a plurality of pixel regions P arranged in a matrix. The pixel region P includes: a binding region BB and a non-binding region BB' surrounding the binding region BB. Each pixel region P includes: a driving back plate 10, a connection electrode 20, an adhesive layer 30, and an auxiliary electrode 40.

Specifically, the connection electrode 20 is disposed at one side of the driving backplate 10 and located in the non-binding region BB' for connecting with the driving backplate 10; the adhesive layer 30 is disposed on the same layer as the connection electrode 20 and located in the binding region BB for binding the light emitting element 50; and an auxiliary electrode 40 for connecting the light emitting element 50 and the connection electrode 20.

In one exemplary embodiment, the connection electrode 20 and the auxiliary electrode 40 may be a metal or a transparent conductive material. The connection electrode 20 and the auxiliary electrode 40 may be made of the same material or may be made of different materials.

In an exemplary embodiment, the connection electrode 20 may have a cylindrical shape or other shape.

In one exemplary embodiment, the orthographic projection of the adhesive layer 30 on the driving backplane 10 covers the orthographic projection of the light emitting elements on the driving backplane 10.

In an exemplary embodiment, the material of which the adhesion layer 30 is made may be polyimide or SU-8 photoresist.

In an exemplary embodiment, the connection electrode 20 and the light emitting element 50 are located at different regions, and the light emitting element 50 and the connection electrode 20 are connected through the auxiliary electrode 40, that is, the alignment accuracy required by the present application is only required to ensure that the light emitting element can be bonded on the adhesive layer, which greatly reduces the accuracy of the device when the light emitting element is transferred and reduces the time consumption required for alignment.

In one exemplary embodiment, the light emitting element may include a Micro LED. The size of the Micro LED is micron, and the Micro LED can be configured in various shapes, for example, the orthographic projection of the Micro LED on the original substrate can be configured to be square, round or trapezoid, etc. Fig. 1 illustrates an example in which the orthogonal projection of the light emitting element on the original substrate is a square.

In an exemplary embodiment, the original substrate may be a sapphire substrate, a silicon substrate, a gallium nitride substrate, or the like, which is not limited in this embodiment.

Fig. 3 is a schematic structural diagram of a carrier substrate according to an exemplary embodiment. As shown in fig. 3, the carrier substrate includes: a substrate 1 and a colloidal layer 2 sequentially disposed on the substrate 1. The colloid layer 2 includes: a release layer 2A and an adhesive layer 2B. The release layer 2A is disposed on the side of the adhesive layer 2B close to the substrate 1.

In an exemplary embodiment, the substrate 1 may be a glass substrate, a plastic substrate, or other transparent substrate.

In an exemplary embodiment, the carrier substrate carries the light emitting element 50 peeled off from the original substrate, wherein the light emitting element 50 is located on the side of the adhesive layer 2B away from the base 1.

Fig. 4 is a schematic structural diagram of a light-emitting element according to an exemplary embodiment. As shown in fig. 4, an exemplary embodiment provides a light emitting element including: the light emitting device includes a buffer layer 51, an N-type semiconductor layer 52, a light emitting layer 53, a P-type semiconductor layer 54, an ohmic contact electrode 55, a first electrode 56, and a second electrode 57, which are sequentially stacked. It will be understood by those skilled in the art that the plurality of light emitting elements are formed on an original substrate by forming a buffer layer 51 on the original substrate, growing an N-type semiconductor layer 52, a light emitting layer 53, and a P-type semiconductor layer 54 on the buffer layer, forming an ohmic electrode in contact with the P-type semiconductor layer, and finally forming a first electrode 56 in contact with the ohmic electrode 55 and a second electrode 57 in contact with the N-type semiconductor layer 52.

As shown in fig. 4, the light-emitting layer 53 includes: a first quantum well layer 531 and a second quantum well layer 532. The second quantum well layer 532 is located on the side of the first quantum well layer 531 away from the buffer layer 51.

In an exemplary embodiment, the buffer layer 51 may be made of silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride. The length of the buffer layer 51 in the direction perpendicular to the original substrate is 2800-.

In one exemplary embodiment, the buffer layer 51 has a length of 3000 nm in a direction perpendicular to the original substrate.

In one exemplary embodiment, the length of the N-type semiconductor layer 52 along the direction perpendicular to the original substrate is 700-900 nm.

In one exemplary embodiment, the length of the N-type semiconductor layer 52 in a direction perpendicular to the original substrate is 800 nm.

In one exemplary embodiment, the length of the first quantum well layer 531 in the direction perpendicular to the original substrate is 200-300 nm.

In one exemplary embodiment, the length of the first quantum well layer 531 in the direction perpendicular to the original substrate is 250 nm.

In one exemplary embodiment, the length of the second quantum well layer 532 in the direction perpendicular to the original substrate is 150-200 nm.

In one exemplary embodiment, the length of the second quantum well layer 532 in the direction perpendicular to the original substrate is 180 nanometers.

In one exemplary embodiment, the length of the P-type semiconductor layer 54 along the direction perpendicular to the original substrate is 100-150 nm.

In one exemplary embodiment, the length of the P-type semiconductor layer 54 in a direction perpendicular to the original substrate is 120 nm.

In one exemplary embodiment, the ohmic contact electrode 55 is made of a metal. The ohmic contact electrode 55 may have a single-layer structure or may have a stacked-layer structure. When the ohmic contact electrode 55 has a stacked-layer structure, the ohmic contact electrode includes: the buffer layer is arranged on the first metal layer.

In one exemplary embodiment, the first metal layer may be made of nickel, and the length of the first metal layer in a direction perpendicular to the original substrate is 4-6 nm.

In one exemplary embodiment, the length of the first metal layer in the direction perpendicular to the original substrate is 5 nm.

In one exemplary embodiment, the second metal layer may be made of gold, and the length of the second metal layer in a direction perpendicular to the original substrate is 4-6 nm.

In one exemplary embodiment, the length of the second metal layer in the direction perpendicular to the original substrate is 5 nm.

In one exemplary embodiment, the first electrode 56 and the second electrode 57 are formed using the same process. The first electrode 56 and the second electrode 57 are made of metal. The structure of the first electrode 56 and the second electrode 57 may be a single layer structure or may be a stacked layer structure. When the first electrode 56 and the second electrode 57 are a stacked structure, the first electrode 56 and the second electrode 57 include: the buffer layer is arranged on the first metal layer, and the buffer layer is arranged on the second metal layer.

In one exemplary embodiment, the third metal layer may be made of titanium, and the length of the third metal layer in a direction perpendicular to the original substrate is 8-12 nm.

In one exemplary embodiment, the length of the third metal layer in the direction perpendicular to the original substrate is 10 nm.

In an exemplary embodiment, the fourth metal layer may be made of gold or silver, and the length of the fourth metal layer in a direction perpendicular to the original substrate is 90-110 nm.

In one exemplary embodiment, the length of the fourth metal layer in a direction perpendicular to the original substrate is 100 nm.

The display substrate is used for binding the light-emitting elements which are borne by the bearing substrate and stripped from the original substrate; the display substrate includes: a plurality of pixel regions arranged in a matrix, the pixel regions including: a binding region and a non-binding region surrounding the binding region, each pixel region including: the driving back plate, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving back plate, is positioned in the non-binding area and is used for being connected with the driving back plate; the adhesion layer and the connection electrode are arranged on the same layer and are positioned in the binding region for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. This application is through bearing the weight of on bearing the weight of the base plate and setting up the binding region at display substrate from the light emitting component that original base plate was peeled off, through auxiliary electrode and connection electrode connection light emitting component and drive backplate, has reduced the counterpoint precision, not only can save time, can save production moreover and rise originally.

In an exemplary embodiment, as shown in fig. 1, the driving back plate 10 includes: a substrate 11, a thin film transistor 12, a first insulating layer 13, a second insulating layer 14, a power supply electrode 15, and a planarization layer 16.

Specifically, the thin film transistor 12 is disposed on one side of the substrate 11, the power supply electrode 15 is disposed on one side of the thin film transistor 12 away from the substrate 11, and the planarization layer 16 is disposed on one side of the power supply electrode 15 away from the substrate 11; the power supply electrode 15 is connected to the drain electrode of the thin film transistor.

In one exemplary embodiment, the substrate 11 may be a rigid substrate or a flexible substrate, wherein the rigid substrate may be, but is not limited to, one or more of glass, a sheet of metal ; the flexible substrate may be, but is not limited to, one or more of polyethylene terephthalate, ethylene terephthalate, polyetheretherketone, polystyrene, polycarbonate, polyarylate, polyimide, polyvinyl chloride, polyethylene, textile fibers.

In one exemplary embodiment, the thin film transistor 12 includes: an active layer, a gate electrode, a source electrode, and a drain electrode. The source electrode and the drain electrode are respectively connected with the active layer. The thin film transistor may be a top gate structure, or a bottom gate structure. Fig. 1 illustrates a thin film transistor as an example of a bottom gate structure.

In one exemplary embodiment, the gate electrode may be made of a metal. The metal may be molybdenum. The length of the gate electrode along the direction perpendicular to the substrate is 150-250 nm.

In one exemplary embodiment, the gate electrode has a length of 200 nm in a direction perpendicular to the substrate.

In an exemplary embodiment, the active layer may be made of a metal oxide or polysilicon. The metal oxide may be indium gallium zinc oxide. The length of the active layer along the direction perpendicular to the substrate is 30-50 nm.

In one exemplary embodiment, the length of the active layer in the direction perpendicular to the substrate is 40 nanometers.

In one exemplary embodiment, the source electrode and the drain electrode may be made of metal. The metal may be molybdenum. The length of the source electrode and the drain electrode along the direction perpendicular to the substrate is 150-250 nm.

In one exemplary embodiment, the length of the source and drain electrodes in a direction perpendicular to the substrate is 200 nanometers.

As shown in fig. 1, a first insulating layer 13 is disposed between the active layer and the gate electrode. A second insulating layer 14 is provided on the side of the source and drain electrodes remote from the substrate 11.

In an exemplary embodiment, the first insulating layer 13 and the second insulating layer 14 may be made of silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

In one exemplary embodiment, the length of the first insulating layer 13 in the direction perpendicular to the substrate is 130-170 nm.

In one exemplary embodiment, the length of the first insulating layer 13 in the direction perpendicular to the substrate is 150 nm.

In one exemplary embodiment, the length of the second insulating layer 14 along the direction perpendicular to the substrate is 280-320 nm.

In one exemplary embodiment, the length of the second insulating layer 14 in the direction perpendicular to the substrate is 300 nanometers.

In one exemplary embodiment, the length of the power supply electrode 15 in the direction perpendicular to the substrate is 350-450 nm.

In one exemplary embodiment, the length of the power supply electrode 15 in the direction perpendicular to the substrate is 400 nm.

In an exemplary embodiment, the material of which the power feeding electrode 15 is made is metal. The structure of the feeding electrode 15 may be a single-layer structure or a stacked-layer structure. When the structure of the feeding electrode 15 is a laminated structure, the feeding electrode 15 includes: and the fifth metal layer, the sixth metal layer and the seventh metal layer are arranged in a laminated manner. The fifth metal layer is arranged on one side of the sixth metal layer close to the substrate, and the seventh metal layer is arranged on one side of the fifth metal layer far away from the substrate.

In an exemplary embodiment, the fifth metal layer and the seventh metal layer may be made of titanium.

In an exemplary embodiment, the sixth metal layer may be made of aluminum.

In one exemplary embodiment, the length of the planarization layer 16 in the direction perpendicular to the substrate is greater than 1.5 microns.

In an exemplary embodiment, the material of the planarization layer 16 may be acrylic-based photoresist or silicone resin.

In an exemplary embodiment, the flat layer is disposed in the driving backplane, so that uniformity of the light emitting elements bound on the driving backplane can be ensured, and display effect of the display substrate is improved.

In one exemplary embodiment, as shown in fig. 1, a first via V1 and a second via V2 are disposed on the planarization layer 16 in each pixel region.

In an exemplary embodiment, the number of the first vias V1 is at least one, and the shape of the cross section of the first via may be a circle, a square, or other shape.

In an exemplary embodiment, the number of the second vias V2 is at least one, and the shape of the cross section of the first via may be a circle, a square, or other shape.

In an exemplary embodiment, as shown in fig. 1, the power supply electrode 15 includes: a first power supply electrode 151 and a second power supply electrode 152, and the second power supply electrode 152 is connected to the drain electrode of the thin film transistor 12.

In one exemplary embodiment, as shown in fig. 1, the connection electrode 20 includes: the first and

second connection electrodes

21 and 22, and the first and

second connection electrodes

21 and 22 are respectively located at both sides of the binding region BB.

The first connection electrode 21 is electrically connected to the first power feeding electrode 151 through the first via V1, and the second connection electrode 22 is electrically connected to the second power feeding electrode 152 through the second via V2.

The light emitting element 50 includes: a first surface and a second surface arranged oppositely; the first electrode 56 and the second electrode 57 are located at the second surface.

In one exemplary embodiment, the adhesive layer 30 is in direct contact with the first surface of the light emitting element 50 when the display substrate binds the light emitting element.

In one exemplary embodiment, the viscosity of the adhesive layer 30 is less than 500 millipascals per second.

In one exemplary embodiment, the thickness of the adhesion layer 30 is less than 100 nanometers.

Fig. 5 is a schematic structural diagram of a display substrate according to an exemplary embodiment. As shown in fig. 5, in each pixel region, the auxiliary electrode includes: a first auxiliary electrode 41 and a second auxiliary electrode 42.

The first auxiliary electrode 41 is used to connect the first electrode 56 and the first connection electrode 21, and the second auxiliary electrode 22 is used to connect the second electrode 57 and the second connection electrode 22.

In an exemplary embodiment, the connection electrode 20 and the auxiliary electrode 40 may be separately provided, or the connection electrode 20 and the auxiliary electrode 40 may be integrally formed.

An embodiment of the present application further provides a manufacturing method of a display substrate, and fig. 6 is a flowchart of the manufacturing method of the display substrate provided in the embodiment of the present application. As shown in fig. 6, the method for manufacturing a display substrate according to the embodiment of the present application is used for manufacturing the display substrate according to the embodiment, and the method for manufacturing a display substrate specifically includes the following steps.

Step S11, forming a driving back plate.

Step S12, forming a connection electrode on the driving back plate.

And step 13, forming an insulating support layer which is located in the non-binding area and used for limiting the binding area on the driving back plate formed with the connecting electrode.

In one exemplary embodiment, an overlapping area exists between the orthographic projection of the insulating support layer on the driving back plate and the orthographic projection of the connecting electrode on the driving back plate.

In one exemplary embodiment, the insulating support layer includes: the first supporting part, the second supporting part and the third supporting part. The orthographic projection of the first supporting part on the driving back plate at least partially covers the orthographic projection of the first connecting electrode on the driving back plate. The orthographic projection of the second supporting part on the driving back plate at least partially covers the second connecting electrode. The third support part is located in the unbonded area, and the second support part and the third support part are used for limiting the bonded area.

In one exemplary embodiment, the length of the insulating support layer in the direction perpendicular to the driving backplane is equal to the length of the light emitting elements in the direction perpendicular to the driving backplane.

In one exemplary embodiment, the first and second supporting parts may not only protect the connection electrodes but also support the carrier substrate when the display substrate is aligned with the carrier substrate. The third support part may not only define the binding region in combination with the second support part, but also support the carrier substrate.

Step S14, forming an adhesive layer on the driving back plate formed with the insulating support layer by using a printing process.

Specifically, step S14 includes: and printing by using polyimide printing equipment in the process flow of the liquid crystal display panel to form the adhesive layer.

And step S15, aligning the carrier substrate and the driving back plate with the adhesive layer formed thereon by using an alignment device, so that the light-emitting elements on the carrier substrate are adhered on the adhesive layer in the binding region.

Step S16, heating the aligned carrier substrate and the driving backplane with the adhesive layer formed thereon, so that the adhesive layer is cured to fix the light emitting element.

Specifically, step S16 includes: and heating the aligned bearing substrate and the driving back plate with the adhesion layer by adopting a post-baking process unit.

And step S17, peeling off the bearing substrate and the insulating support layer in sequence to expose the connecting electrode.

Step S18 is to form an auxiliary electrode connecting the light emitting element and the connection electrode.

The display substrate is provided in the foregoing embodiments, and the implementation principle and the implementation effect thereof are similar, and are not described herein again.

In an exemplary embodiment, step S11 includes: providing a substrate; forming a thin film transistor on a substrate; forming a power supply electrode including a first power supply electrode and a second power supply electrode on a side of the thin film transistor away from the substrate; a planarization layer including a first via hole and a second via hole is formed on a side of the power supply electrode away from the thin film transistor.

In one exemplary embodiment, forming a thin film transistor on a substrate includes: depositing a first metal film on a substrate, and patterning the first metal film through a patterning process to form a gate electrode; depositing a first insulating film on a glass substrate with a gate electrode, and patterning the first insulating film through a patterning process to form a first insulating layer; forming an active layer on the gate insulating layer; depositing a second metal film on the glass substrate on which the active layer is formed, and patterning the second metal film through a patterning process to form a source drain electrode; and depositing a first insulating film on the stripping substrate for forming the source and drain electrodes, and patterning the first insulating film through a patterning process to form a second insulating layer.

In one exemplary embodiment, forming the power supply electrode including the first power supply electrode and the second power supply electrode on the side of the thin film transistor away from the substrate includes: and depositing a third metal film on the second insulating layer, and patterning the third metal film through a patterning process to form a power supply electrode comprising a first power supply electrode and a second power supply electrode.

In one exemplary embodiment, forming the planarization layer including the first via hole and the second via hole at a side of the power supply electrode away from the thin film transistor includes: and coating a flat film on the side of the power supply electrode, which is far away from the thin film transistor, and patterning the flat film through a photoetching process to form a flat layer.

In an exemplary embodiment, before depositing the first metal thin film on the substrate, the method of fabricating the display substrate further includes: and cleaning the substrate.

In an exemplary embodiment, step S16 includes: and heating the aligned bearing substrate and the original display substrate with the original adhesion layer, wherein the heating time is 25-35 minutes, and the heating temperature is 200-230 ℃.

In one exemplary embodiment, peeling the carrier substrate includes: and stripping the bearing substrate by adopting a laser process and a physical stripping process.

The carrier substrate includes: the base, the release layer and the adhesion layer are arranged in a stacked mode. Peeling off the carrier substrate includes: stripping the substrate by adopting a laser process; stripping the release layer by adopting a line scanning laser process; and stripping the adhesive layer by chemical dissolution or physical stripping.

In one exemplary embodiment, peeling the insulating support layer comprises: and stripping the insulating support layer by adopting a plasma etching process, wherein the etching time is 20-40 minutes.

In one exemplary embodiment, peeling the insulating support layer comprises: and stripping the insulating supporting layer by adopting an oxygen plasma etching process.

In an exemplary embodiment, when the connection electrode and the auxiliary electrode are integrally formed, the method of manufacturing the display substrate includes: forming a driving back plate; forming an insulating support layer on the driving back plate, wherein the insulating support layer is positioned in the non-binding area and used for limiting the binding area; forming an adhesion layer on the driving back plate with the insulating support layer by adopting a printing process; aligning the bearing substrate and the driving back plate with the adhesive layer by using alignment equipment, so that the light-emitting element on the bearing substrate is adhered to the adhesive layer in the binding area; heating the aligned bearing substrate and the drive backboard with the adhesive layer to cure the adhesive layer so as to fix the light-emitting element; sequentially stripping the bearing substrate and the insulating support layer to expose the through hole of the flat layer; a connection electrode and an auxiliary electrode are formed.

The following will further illustrate the method of fabricating the substrate in conjunction with fig. 1, 2, and 7-15.

Step S111, providing a substrate 11, cleaning the substrate 11, depositing a first metal film on the substrate 11, and patterning the first metal film through a patterning process to form a gate electrode; depositing a first insulating film on the glass substrate on which the gate electrode is formed, and patterning the first insulating film by a patterning process to form a first insulating layer 13; forming an active layer on the gate insulating layer; depositing a second metal film on the glass substrate on which the active layer is formed, and patterning the second metal film through a patterning process to form a source drain electrode; a first insulating film is deposited on the lift-off substrate on which the source and drain electrodes are formed, and the first insulating film is patterned by a patterning process to form a second insulating layer 14 to form the thin film transistor 12, as shown in fig. 7.

Step S112, depositing a third metal film on the second insulating layer 14, and patterning the third metal film through a patterning process to form the power supply electrode 15 including the first power supply electrode 151 and the second power supply electrode 152, as shown in fig. 8.

Step S113, coating a flat film on the side of the power supply electrode 15 away from the thin film transistor 12, patterning the flat film through a photolithography process, and forming a flat layer 16 including a first via hole V1 and a second via hole V2 to form the driving backplate 10, as shown in fig. 9.

Step S114, forming the connection electrode 20 including the first connection electrode 21 and the second connection electrode 22 on the driving back plate 10, as shown in fig. 10.

Step S115, forming an insulating support layer 60 located in the non-binding region and used for defining the binding region on the driving back plate 10 formed with the connection electrode 20, as shown in fig. 11.

Step S116, using a polyimide printing apparatus in the process flow of the liquid crystal display panel, forms the adhesive layer 30 on the driving backplane 10 formed with the insulating support layer 60 using a printing process, as shown in fig. 12.

Step S117, aligning the carrier substrate 100 and the driving backplane 10 with the adhesive layer 30 formed thereon by using an alignment apparatus, so that the light emitting element 50 on the carrier substrate is adhered on the adhesive layer 30 located in the binding region BB, and heating the aligned carrier substrate and the driving backplane 10 with the adhesive layer 30 formed thereon by using a post-baking process unit, so that the adhesive layer 30 is cured, wherein the heating time is 25 to 35 minutes, and the heating temperature is 200 and 230 degrees celsius, so as to fix the light emitting element 50, as shown in fig. 13.

Step S118, sequentially stripping the base 1 and the release layer 2A in the carrier substrate by using a laser process, as shown in fig. 14.

Step S119, stripping the adhesive layer 2B by chemical dissolution or physical stripping, as shown in FIG. 15.

Step S120, etching the insulating support layer 60 for 20-40 minutes by using a plasma etching process to peel off the insulating support layer 60 and expose the connection electrode 20, as shown in fig. 1.

Step S121, forming the auxiliary electrode 40 connecting the light emitting element 50 and the connection electrode 20, as shown in fig. 2.

The embodiment of the present application further provides a method for transferring a light emitting element, and fig. 16 is a flowchart of the method for transferring a light emitting element provided in the embodiment of the present application. As shown in fig. 16, the method for transferring a light emitting element provided in the embodiment of the present application specifically includes the following steps:

and S21, forming a bearing substrate.

In an exemplary embodiment, step S210 includes: providing a substrate, forming a release layer on the substrate, and forming an adhesive layer on the release layer.

And S22, bonding the bearing substrate and the original substrate, and irradiating the side of the original substrate far away from the bearing substrate by adopting a laser process so as to strip the light-emitting element from the original substrate.

In one exemplary embodiment, the surface of the carrier substrate on which the adhesive layer is located is attached to the surface of the original substrate on which the light emitting device is disposed.

In one exemplary embodiment, a 248 nm or 193 nm laser is used to lift off the light emitting elements from the original substrate.

In one exemplary embodiment, the carrier substrate selectively carries the light emitting elements on the original substrate. The arrangement of the light emitting elements on the original substrate is different from the arrangement of the light emitting elements carried on the carrying substrate.

Step S23, transferring the light emitting element carried on the carrier substrate to the display substrate by using the display substrate manufacturing method.

In one exemplary embodiment, the light emitting element may include a Micro LED. The size of the Micro LED is micron, and the Micro LED can be configured in various shapes, for example, the orthographic projection of the Micro LED on the original substrate can be configured to be square, round or trapezoid, etc.

The manufacturing method of the display substrate is the manufacturing method of the display substrate provided in the foregoing embodiment, and the display substrate is the display substrate provided in the foregoing embodiment, so that the implementation principle and the implementation effect are similar, and are not described herein again.

A method for transferring a light emitting element provided by an exemplary embodiment is further described below with reference to fig. 17 to 19.

In step 211, a carrier substrate 100 is formed, as shown in fig. 17.

The carrier substrate 100 includes: the substrate 1, the release layer 2A and the adhesive layer 2B are stacked.

Step 212, the carrier substrate 100 is attached to the original substrate 200, as shown in fig. 18.

The original substrate 200 is provided with a plurality of light emitting elements 50.

Step 213, irradiating the original substrate 200 far from the carrier substrate 100 by using a laser process to peel the light emitting element 50 from the original substrate 200, and transferring the original substrate 200, as shown in fig. 19.

Step 214, using steps S111-S121 in the foregoing embodiments, transfers the light emitting elements on the carrier substrate into the display substrate.

The drawings of the embodiments of the present application relate only to the structures related to the embodiments of the present application, and other structures may refer to general designs.

In the drawings used to describe embodiments of the present application, the thickness and dimensions of layers or microstructures are exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.

Although the embodiments disclosed in the present application are described above, the descriptions are only for the convenience of understanding the present application, and are not intended to limit the present application. 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 disclosure as defined by the appended claims.

Claims

1. The display substrate is characterized in that the display substrate is used for binding light-emitting elements which are borne by a bearing substrate and are stripped from an original substrate; the display substrate includes: a plurality of pixel regions arranged in a matrix, the pixel regions including: a binding region and a non-binding region surrounding the binding region, each pixel region including: the driving back plate, the connecting electrode, the adhesion layer and the auxiliary electrode;

2. The display substrate of claim 1, wherein the driving backplane comprises: a substrate, a thin film transistor, a power supply electrode and a flat layer;

3. The display substrate according to claim 2, wherein in each pixel region, a first via hole and a second via hole are provided on the planarization layer;

4. The display substrate according to claim 3, wherein the light-emitting element comprises: a first electrode and a second electrode, the light emitting element including: a first surface and a second surface arranged oppositely; the first electrode and the second electrode are positioned on the second surface;

5. The display substrate according to claim 4, wherein in each pixel region, the auxiliary electrode comprises: a first auxiliary electrode and a second auxiliary electrode;

6. The display substrate according to claim 1, wherein the connection electrode and the auxiliary electrode are integrally formed.

7. A method of manufacturing a display substrate, for manufacturing a display substrate according to any one of claims 1 to 6, the method comprising:

forming a driving back plate;

forming a connection electrode on the driving back plate;

8. The method of claim 7, wherein forming a driving back plate comprises:

providing a substrate;

forming a thin film transistor on the substrate;

9. The method of claim 8, wherein the heating the aligned carrier substrate and the driving back plate with the adhesive layer formed thereon comprises:

10. The method of claim 8, wherein the peeling the carrier substrate comprises:

11. The method of claim 8, wherein peeling the insulating support layer comprises:

12. A method of transferring a light emitting element, the method comprising:

providing a bearing substrate;

transferring the light emitting element carried on the carrier substrate into the display substrate according to any one of claims 1 to 6 by using the method for manufacturing a display substrate according to any one of claims 7 to 11.