CN113451346B

CN113451346B - Display substrate, manufacturing method thereof and transfer method of light-emitting element

Info

Publication number: CN113451346B
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: 2024-03-01
Anticipated expiration: 2040-03-27
Also published as: CN113451346A

Abstract

The display substrate is used for binding the light-emitting element which is carried by the carrying substrate and is stripped from the original substrate; the display substrate includes: a plurality of pixel areas arranged in a matrix, the pixel areas including: a binding region and an unbinding region surrounding the binding region, each pixel region including: the driving backboard, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving backboard and is positioned in the unbound area and used for being connected with the driving backboard; the adhesion layer and the connecting electrode are arranged on the same layer and are positioned in the binding area and used for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. The method and the device can save time and 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 method for manufacturing the display substrate, and a method for transferring a light emitting element.

Background

Light emitting diode (Light Emitting Diode, LED) technology has evolved for nearly thirty years from an initial solid state lighting power supply to a backlight source in the display area to an LED display screen, providing a solid foundation for its wider application. With the development of chip manufacturing and packaging technologies, sub-millimeter light emitting diodes (Mini Light Emitting Diode, abbreviated as Mini LEDs) of about 50 micrometers to 60 micrometers and Micro light emitting diodes (Micro Light Emitting Diode, abbreviated as Micro LEDs) of less than 15 micrometers are displayed gradually becoming a hot spot of a display panel. The Micro LED display has the remarkable advantages of low power consumption, high color gamut, high stability, high resolution, ultra-thin performance, easy realization of flexible display and the like, and is expected to become a better display technology for replacing organic light emitting diode display (Organic Light Emitting Diode, OLED for short).

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

Content of the 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 the generation cost.

In a first aspect, the present application provides a display substrate for binding a light emitting element that is carried by a carrier substrate and is peeled off from an original substrate; the display substrate includes: a plurality of pixel areas arranged in a matrix, the pixel areas comprising: a binding region and an unbinding region surrounding the binding region, each pixel region including: the driving backboard, the connecting electrode, the adhesion layer and the auxiliary electrode;

the connecting electrode is arranged on one side of the driving backboard and is positioned in the unbound area and used for being connected with the driving backboard; the adhesion layer and the connecting electrode are arranged on the same layer and are positioned in a binding area 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 planarization 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 away from the substrate, and the flat layer is arranged on one side of the power supply electrode away from the substrate; the power supply electrode is connected with the drain electrode of the thin film transistor;

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

In one possible implementation, in each pixel region, the flat layer is provided with a first via hole and a second via hole;

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 at two sides of the binding area;

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 comprising: a first surface and a second surface disposed opposite each other; 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 adhesion layer has a viscosity of less than 500 millipascals per second and a thickness of 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, which is used for manufacturing the display substrate, and the method includes:

forming a driving backboard;

forming a connection electrode on the driving back plate;

forming an insulating support layer which is positioned in the unbound area and used for limiting the bound area on the driving backboard provided with the connecting electrode; an overlapping area exists between the orthographic projection of the insulating support layer on the driving backboard and the orthographic projection of the connecting electrode on the driving backboard;

Forming an adhesion layer on the driving backboard with the insulating support layer by adopting a printing process;

aligning the bearing substrate with the driving backboard provided with the adhesion layer by adopting alignment equipment, so that the light-emitting element on the bearing substrate is adhered to the adhesion layer positioned in the binding area;

heating the aligned bearing substrate and the driving backboard with the formed adhesive layer to enable the adhesive layer to be solidified 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 back plate includes:

providing a substrate;

forming a thin film transistor on the 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;

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 back plate with the adhesive layer formed includes:

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

In one possible implementation, the peeling carrier substrate includes:

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

In one possible implementation, the stripping 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 further provides a method for transferring a light emitting element, the method including:

providing a bearing substrate;

attaching the bearing substrate and the original substrate, and irradiating one side of the original substrate 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 transferring method of a light-emitting element, wherein the display substrate is used for binding the light-emitting element which is born by a bearing substrate and is peeled off from an original substrate; the display substrate includes: a plurality of pixel areas arranged in a matrix, the pixel areas including: a binding region and an unbinding region surrounding the binding region, each pixel region including: the driving backboard, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving backboard and is positioned in the unbound area and used for being connected with the driving backboard; the adhesion layer and the connecting electrode are arranged on the same layer and are positioned in the binding area and used for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. According to the light-emitting element and the driving backboard, the light-emitting element which is peeled off from the original substrate is arranged in the binding area of the display substrate, and the auxiliary electrode and the connecting electrode are connected with the light-emitting element and the driving backboard, so that the alignment precision is reduced, the high-precision alignment equipment is avoided, the time is saved, and the production cost is saved.

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 practice of the application. Other advantages of the present application may be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The accompanying drawings are included to provide an understanding of the technical aspects of the present application, and are incorporated in and constitute a part of this specification, illustrate the technical aspects of the present application and together with the examples of the present application, and not constitute a limitation of the technical aspects of the present application.

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 a pixel region of FIG. 1;

FIG. 3 is a schematic view 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 structural diagram 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 for manufacturing 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 illustrating a transfer method of a light emitting element according to an exemplary embodiment.

Detailed Description

The present application describes a number of embodiments, but the description is illustrative and not 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 in place of any other feature or element of any other embodiment unless specifically limited.

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 of the present disclosure may also be combined with any conventional features or elements to form a unique claim as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other claims to form another unique claim as defined in 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 to be restricted except in light of the attached claims and their equivalents. Further, various modifications and changes may be made within the scope of the appended claims.

Furthermore, 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 sequences of steps are possible as will be appreciated by those of ordinary skill in the art. Accordingly, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. Furthermore, 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 in the disclosure of the embodiments of the present application should be given the ordinary meaning as understood by one of ordinary skill in the art to which the present application belongs. The terms "first," "second," and the like, as used in embodiments of the present application, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to denote relative positional relationships, which may also change accordingly when the absolute position of the object being described changes.

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

Specifically, the connection electrode 20 is disposed at one side of the driving back plate 10 and located in the unbound region BB' for connection with the driving back plate 10; the adhesion layer 30 is disposed on the same layer as the connection electrode 20 and is located in the binding region BB for binding the light emitting element 50; 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 metal or transparent conductive material. The connection electrode 20 and the auxiliary electrode 40 may be made of the same material or may be different.

In one exemplary embodiment, the shape of the connection electrode 20 may be a column or other shape.

In an exemplary embodiment, the orthographic projection of the adhesive layer 30 on the driving backplate 10 covers the orthographic projection of the light emitting element on the driving backplate 10.

In one exemplary embodiment, the adhesive layer 30 may be made of polyimide or SU-8 photoresist.

In an exemplary embodiment, the connection electrode 20 and the light emitting element 50 are located in different areas, and the light emitting element 50 and the connection electrode 20 are connected through the auxiliary electrode 40, that is, the alignment accuracy required in the present application is only required to ensure that the light emitting element can be bound to the adhesive layer, so that the accuracy of the device when the light emitting element is transferred is greatly reduced, and the time required for alignment is reduced.

In one exemplary embodiment, the light emitting element may include a Micro LED. The Micro LED is in a micrometer size, and the Micro LED can be arranged in various shapes, for example, the orthographic projection of the Micro LED on the original substrate is square, round or trapezoid. Fig. 1 illustrates an example in which the front projection of the light emitting element on the original substrate is 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 any way by the embodiments of the present application.

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 gel layer 2 sequentially disposed on the substrate 1. The gel layer 2 includes: a release layer 2A and an adhesive layer 2B. The release layer 2A is provided 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 at a side of the adhesive layer 2B away from the base 1.

Fig. 4 is a schematic structural view of a light emitting element according to an exemplary embodiment. As shown in fig. 4, a light emitting element provided by an exemplary embodiment includes: the buffer layer 51, the N-type semiconductor layer 52, the light emitting layer 53, the P-type semiconductor layer 54, the ohmic contact electrode 55, the first electrode 56, and the second electrode 57 are stacked in this order. It should be understood by those skilled in the art that the manufacturing process of the plurality of light emitting elements is to form the buffer layer 51 on the original substrate, grow the N-type semiconductor layer 52, the light emitting layer 53, the P-type semiconductor layer 54 on the buffer layer, then form the ohmic electrode contacting the P-type semiconductor layer, and finally form the first electrode 56 contacting the ohmic electrode 55 and the second electrode 57 contacting the N-type semiconductor layer 52, thereby forming the plurality of light emitting elements on the original substrate.

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 at a side of the first quantum well layer 531 remote 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 buffer layer 51 has a length of 2800-3200 nm in a direction perpendicular to the original substrate.

In one exemplary embodiment, the buffer layer 51 has a length of 3000 nanometers 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 nanometers.

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

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

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

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

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

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

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

In one exemplary embodiment, the ohmic contact electrode 55 is made of metal. The ohmic contact electrode 55 may have a single-layer structure or a stacked-layer structure. When the ohmic contact electrode 55 is of a stacked structure, the ohmic contact electrode includes: the first metal layer and the second metal layer are positioned on one side of the first metal layer far away from the buffer layer.

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

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

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

In one exemplary embodiment, the second metal layer has a length of 5 nanometers in a direction perpendicular to the original substrate.

In an 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 structures 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 in a stacked structure, the first electrode 56 and the second electrode 57 include: the third metal layer and the fourth metal layer are positioned on one side of the third metal layer far away from the buffer layer.

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

In one exemplary embodiment, the third metal layer has a length of 10 nanometers in a direction perpendicular to the original substrate.

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

In one exemplary embodiment, the length of the fourth metal layer along the direction perpendicular to the original substrate is 100 nanometers.

The display substrate is used for binding the light-emitting elements which are carried by the carrying substrate and are stripped from the original substrate; the display substrate includes: a plurality of pixel areas arranged in a matrix, the pixel areas including: a binding region and an unbinding region surrounding the binding region, each pixel region including: the driving backboard, the connecting electrode, the adhesion layer and the auxiliary electrode; the connecting electrode is arranged on one side of the driving backboard and is positioned in the unbound area and used for being connected with the driving backboard; the adhesion layer and the connecting electrode are arranged on the same layer and are positioned in the binding area and used for binding the light-emitting element; and an auxiliary electrode for connecting the light emitting element and the connection electrode. According to the light-emitting element and the driving backboard, the light-emitting element which is peeled off from the original substrate is arranged in the binding area of the display substrate, and the auxiliary electrode and the connecting electrode are connected with the light-emitting element and the driving backboard, so that the alignment precision is reduced, the time can be saved, and the production cost can be saved.

In one 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 flat 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, metal sheets; 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 connected to the active layer, respectively. 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 gate electrode has a length of 150-250 nm in a direction perpendicular to the substrate.

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

In an exemplary embodiment, the active layer may be made of 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 active layer has a length of 40 nanometers in a direction perpendicular to the substrate.

In one exemplary embodiment, the source and drain electrodes 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 nanometers.

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

As shown in fig. 1, a first insulating layer 13 is disposed between the active layer and the gate electrode. The 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 to 170 nanometers.

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 second insulating layer 14 has a length in a direction perpendicular to the substrate of 280-320 nanometers.

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

In one exemplary embodiment, the length of the powered electrode 15 along the direction perpendicular to the substrate is 350-450 nanometers.

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

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

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

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

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

In one exemplary embodiment, the planarizing layer 16 may be made of an acrylic-based photolithographic resin or a silicone resin.

In an exemplary embodiment, the flat layer is disposed in the driving back plate to ensure uniformity of the light emitting elements bound on the driving back plate, thereby improving display effect of the display substrate.

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 circular, square, or other shape.

In an exemplary embodiment, as shown in fig. 1, the power supply electrode 15 includes: the first power supply electrode 151 and the 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 connection electrode 21 and the second connection electrode 22, the first connection electrode 21 and the second connection electrode 22 being located at both sides of the bonding region BB, respectively.

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

The light emitting element 50 includes: a first surface and a second surface disposed opposite each other; the first electrode 56 and the second electrode 57 are located on the second surface.

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

In one exemplary embodiment, the adhesion layer 30 has a viscosity of 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.

The embodiment of the application also provides a manufacturing method of the display substrate, and fig. 6 is a flowchart of the manufacturing method of the display substrate provided by the embodiment of the application. As shown in fig. 6, the method for manufacturing a display substrate provided in the embodiment of the present application is used for manufacturing the display substrate provided in the foregoing embodiment, and the method for manufacturing a display substrate specifically includes the following steps.

Step S11, a driving backboard is formed.

Step S12, forming a connection electrode on the driving backboard.

And S13, forming an insulating supporting layer which is positioned in the non-binding area and used for limiting the binding area on the driving backboard provided with the connecting electrode.

In one exemplary embodiment, there is an overlap area between the orthographic projection of the insulating support layer on the drive backplate and the orthographic projection of the connection electrode on the drive backplate.

In one exemplary embodiment, the insulating support layer includes: the first support portion, the second support portion, and the third support portion. The front projection of the first supporting part on the driving backboard at least partially covers the front projection of the first connecting electrode on the driving backboard. The orthographic projection of the second supporting part on the driving backboard at least partially covers the second connecting electrode. The third support portion is located in the unbound region, and the second support portion and the third support portion are configured to define the bound region.

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

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

And S14, forming an adhesion layer on the driving backboard with the insulating support layer by adopting a printing process.

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

And S15, aligning the bearing substrate and the driving backboard with the adhesive layer by using an aligning device, so that the light-emitting element on the bearing substrate is adhered to the adhesive layer in the binding area.

And S16, heating the aligned bearing substrate and the driving backboard with the adhesive layer, so that the adhesive layer is solidified, and the light-emitting element is fixed.

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

Step S17, the bearing substrate and the insulating supporting layer are sequentially stripped to expose the connecting electrode.

Step S18, forming an auxiliary electrode for connecting the light emitting element and the connection electrode.

The display substrate provided in the foregoing embodiments has similar implementation principles and implementation effects, and is 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 flat 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 the glass substrate with the gate electrode formed thereon, and patterning the first insulating film by 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 electrode and a drain electrode; and depositing a first insulating film on the stripping substrate for forming the source electrode and the drain electrode, and patterning the first insulating film through a patterning process to form a second insulating layer.

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

In one exemplary embodiment, the method of fabricating a display substrate before depositing the first metal film on the substrate further includes: the substrate is cleaned.

In an exemplary embodiment, step S16 includes: and heating the aligned bearing substrate and the original display substrate with the original adhesive 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: a substrate, a release layer and an adhesive layer are laminated. The peeling support substrate includes: stripping the substrate by adopting a laser process; stripping the release layer by adopting a line scanning laser process; the adhesive layer is peeled off by chemical dissolution or physical tearing.

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

In one exemplary embodiment, when the connection electrode and the auxiliary electrode are integrally formed, the manufacturing method of the display substrate includes: forming a driving backboard; forming an insulating support layer which is positioned in the unbound region and used for limiting the bound region on the driving backboard; forming an adhesion layer on the driving backboard with the insulating support layer by adopting a printing process; aligning the bearing substrate with the driving backboard provided with the adhesion layer by adopting alignment equipment, so that the light-emitting element on the bearing substrate is adhered to the adhesion layer positioned in the binding area; heating the aligned bearing substrate and the driving backboard with the adhesive layer formed thereon, so that the adhesive layer is solidified to fix the light-emitting element; sequentially stripping the bearing substrate and the insulating support layer to expose the flat layer via hole; the connection electrode and the auxiliary electrode are formed.

The method for manufacturing the display substrate is further described below with reference to fig. 1, 2, and 7 to 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 by a patterning process to form a gate electrode; depositing a first insulating film on the glass substrate on which the gate electrode is formed, 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 electrode and a 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, so as to form a 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 by 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.

In step S113, a flat film is coated on a side of the power supply electrode 15 away from the thin film transistor 12, and the flat film is patterned by a photolithography process to form a flat layer 16 including a first via hole V1 and a second via hole V2, so as to form the driving back plate 10, as shown in fig. 9.

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

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

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

In step S117, the alignment device is used to align the carrier substrate 100 with the driving back plate 10 with the adhesive layer 30 formed thereon, so that the light emitting element 50 on the carrier substrate is adhered to the adhesive layer 30 located in the binding area BB, and the post-baking process unit is used to heat the aligned carrier substrate and the driving back plate 10 with the adhesive layer 30 formed thereon, so that the adhesive layer 30 is cured for 25-35 minutes at a heating temperature of 200-230 ℃ to fix the light emitting element 50, as shown in fig. 13.

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

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

In step S120, a plasma etching process is used to etch the insulating support layer 60 for 20-40 minutes to peel off the insulating support layer 60, exposing 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 application also provides a method for transferring the light-emitting element, and fig. 16 is a flowchart of the method for transferring the light-emitting element provided in the embodiment of the 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:

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 one side, far away from the bearing substrate, of the original substrate by adopting a laser process so as to peel 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 bonded to the surface of the original substrate on which the light emitting element is disposed.

In one exemplary embodiment, 248 nm or 193 nm laser is used to peel the light emitting element from the original substrate.

In one exemplary embodiment, the carrier substrate selectively carries the light emitting elements on the original substrate. The light emitting elements on the original substrate are arranged in a different manner from the light emitting elements carried on the carrier substrate.

Step S23, transferring the light-emitting element carried on the carrying substrate to the display substrate by adopting the manufacturing method of the display substrate.

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

The manufacturing method of the display substrate is the manufacturing method of the display substrate provided by the foregoing embodiment, and the display substrate is the display substrate provided by the foregoing embodiment, so that the implementation principle and the implementation effect are similar, and are not repeated here.

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

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

Wherein, the carrier substrate 100 comprises: 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.

Wherein a plurality of light emitting elements 50 are disposed on the original substrate 200.

In step 213, the side of the original substrate 200 away from the carrier substrate 100 is irradiated by a laser process to peel the light emitting element 50 from the original substrate 200, and the original substrate 200 is transferred, as shown in fig. 19.

Step 214, transferring the light emitting element on the carrier substrate to the display substrate by using steps S111-S121 in the previous embodiments.

The drawings in the embodiments of the present application relate only to the structures to which the embodiments of the present application relate, and reference may be made to the general design for other structures.

In the drawings used to describe embodiments of the present application, the thickness and size 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 embodiments are only used for facilitating understanding of the present application, and are not intended to limit the present application. Any person skilled in the art to which this application pertains will be able to make any modifications and variations in form and detail of implementation without departing from the spirit and scope of the disclosure, but the scope of the application is still subject to the scope of the claims appended hereto.

Claims

1. The display substrate is characterized by being used for binding the light-emitting elements which are carried by the carrying substrate and are peeled off from the original substrate; the display substrate includes: a plurality of pixel areas arranged in a matrix, the pixel areas comprising: a binding region and an unbinding region surrounding the binding region, each pixel region including: the driving backboard, the connecting electrode, the adhesion layer and the auxiliary electrode;

the connecting electrode is arranged on one side of the driving backboard and is positioned in the unbound area and used for being connected with the driving backboard; the adhesion layer and the connecting electrode are arranged on the same layer and are positioned in a binding area for binding the light-emitting element; the auxiliary electrode is used for connecting the connecting electrode and the light-emitting element;

the orthographic projection of the adhesive layer on the driving backboard covers the orthographic projection of the light-emitting element on the driving backboard;

the drive back plate includes: a substrate, a thin film transistor, a power supply electrode, and a planarization 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 away from the substrate, and the flat layer is arranged on one side of the power supply electrode away from the substrate; the power supply electrode is connected with the drain electrode of the thin film transistor;

The light emitting element includes: a first electrode and a second electrode, the light emitting element comprising: a first surface and a second surface disposed opposite each other; the first electrode and the second electrode are positioned on the second surface; the adhesion layer is in direct contact with the first surface of the light emitting element.

2. The display substrate of claim 1, wherein the flat layer has a length in a direction perpendicular to the substrate of greater than 1.5 microns.

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. A display substrate according to claim 3, wherein the adhesion layer has a viscosity of less than 500 mpa per second and a thickness of less than 100 nm.

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 backboard; the drive back plate includes: a substrate, a thin film transistor, a power supply electrode, and a planarization 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 away from the substrate, and the flat layer is arranged on one side of the power supply electrode away from the substrate; the power supply electrode is connected with the drain electrode of the thin film transistor;

forming a connection electrode on the driving back plate;

aligning the bearing substrate with the driving backboard provided with the adhesion layer by adopting alignment equipment, so that the light-emitting element on the bearing substrate is adhered to the adhesion layer positioned in the binding area; the light emitting element includes: a first electrode and a second electrode, the light emitting element comprising: a first surface and a second surface disposed opposite each other; 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;

heating the aligned bearing substrate and the driving backboard with the formed adhesive layer to enable the adhesive layer to be solidified so as to fix the light-emitting element; the orthographic projection of the adhesive layer on the driving backboard covers the orthographic projection of the light-emitting element on the driving backboard;

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

providing a substrate;

forming a thin film transistor on the substrate;

9. The method of claim 8, wherein heating the aligned carrier substrate and the drive 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 the stripping the insulating support layer comprises:

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

providing a bearing substrate;

A method of manufacturing a display substrate according to any one of claims 7 to 11, wherein the light-emitting element carried on the carrier substrate is transferred to the display substrate according to any one of claims 1 to 6.