阅读说明：本技术 量子点发光结构及其制作方法和显示装置 (Quantum dot light-emitting structure, manufacturing method thereof and display device ) 是由 梅文海 于 2020-05-27 设计创作，主要内容包括：一种量子点发光结构及其的制作方法和显示装置。该量子点发光结构的制作方法包括：将包括表面修饰有第一配体的第一量子点和光致配体去除剂的第一量子点溶液涂覆在衬底基板上以形成第一量子点发光材料层；对第一量子点发光材料层进行部分曝光,以使得第一量子点发光材料层包括被曝光的部分和未被曝光的部分,光致配体去除剂被配置为在光照下释放配体去除剂,以将第一量子点发光材料层包括被曝光的部分中的第一配体去除；以及采用第一冲洗溶剂对曝光后的第一量子点发光材料层进行显影冲洗以形成第一量子点发光层。由此,该量子点发光结构的制作方法可保证第一量子点发光层的发光性能。(A quantum dot light-emitting structure, a manufacturing method thereof and a display device are provided. The manufacturing method of the quantum dot light-emitting structure comprises the following steps: coating a first quantum dot solution which comprises first quantum dots with surfaces modified with first ligands and a photoinduced ligand remover on a substrate to form a first quantum dot luminescent material layer; partially exposing the first quantum dot light-emitting material layer such that the first quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photobase removing agent being configured to release the ligand removing agent under illumination to remove the first ligands in the portions of the first quantum dot light-emitting material layer including the exposed portions; and developing and washing the exposed first quantum dot luminescent material layer by adopting a first washing solvent to form a first quantum dot luminescent layer. Therefore, the manufacturing method of the quantum dot light-emitting structure can ensure the light-emitting performance of the first quantum dot light-emitting layer.)

1. A manufacturing method of a quantum dot light-emitting structure comprises the following steps:

providing a first quantum dot solution, wherein the first quantum dot solution comprises a first quantum dot with a surface modified with a first ligand and a photoinduced ligand remover, and the first ligand is dissolved in a first washing solvent;

coating the first quantum dot solution on a substrate to form a first quantum dot luminescent material layer;

partially exposing the first quantum dot light-emitting material layer such that the first quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photo-induced ligand removal agent configured to release a ligand removal agent under illumination to remove the first ligand in the exposed portions of the first quantum dot light-emitting material layer; and

and developing and washing the exposed first quantum dot luminescent material layer by using the first washing solvent to form a first quantum dot luminescent layer.

2. The method of claim 1, wherein the photogenerator is a photogenerator.

3. The method of manufacturing a quantum dot light-emitting structure according to claim 2, wherein the photoacid generator includes at least one of a triazine compound, an iodonium compound, a sulfonium compound, and a perfluorobutyl compound.

4. The method of claim 2, wherein in the first quantum dot solution, the ratio of the mass percent of the photoligand-removing agent to the first quantum dot with the surface modified with the first ligand is in the range of 4% to 6%.

5. The method for manufacturing a quantum dot light-emitting structure according to any one of claims 1 to 4, wherein the first rinsing solvent includes at least one of aromatic hydrocarbons such as toluene, xylene, and chlorobenzene.

6. The method for manufacturing the quantum dot light-emitting structure according to any one of claims 1 to 4, wherein the partially exposing the first quantum dot light-emitting material layer comprises:

partially exposing the first quantum dot light-emitting material layer with ultraviolet light having energy of 90-500mJ/cm to form the exposed portion and the unexposed portion²Within the range of (a).

7. The method for fabricating a quantum dot light-emitting structure according to any one of claims 1 to 4, further comprising:

and annealing the substrate base plate formed with the first quantum dot light-emitting layer, wherein the annealing temperature is in the range of 80-180 ℃, and the annealing time is in the range of 5-30 minutes.

8. The method for fabricating the quantum dot light-emitting structure according to any one of claims 1 to 4, wherein the first quantum dot light-emitting layer is configured to emit light with a wavelength ranging from 492-455 nm.

9. The method for fabricating a quantum dot light-emitting structure according to any one of claims 1 to 4, further comprising:

providing a second quantum dot solution, wherein the second quantum dot solution comprises a second quantum dot with a surface modified with a second ligand and a photoinduced ligand remover, and the second ligand is dissolved in a second washing solvent;

coating the second quantum dot solution on the substrate with the first quantum dot light-emitting layer to form a second quantum dot light-emitting material layer;

partially exposing the second quantum dot light-emitting material layer such that the second quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photo-induced ligand removal agent configured to release a ligand removal agent under illumination to remove the second ligand in the exposed portions of the second quantum dot light-emitting material layer; and

and developing and washing the exposed second quantum dot luminescent material layer by using the second washing solvent to form a second quantum dot luminescent layer.

10. The method of claim 9, wherein the second ligand is the same material as the first ligand, and the second rinsing solvent is the same material as the first rinsing solvent.

11. The fabrication method of the quantum dot light-emitting structure according to any one of claims 1 to 4, wherein before forming the first quantum dot light-emitting material layer on the substrate base plate, the fabrication method further comprises:

forming a first photoresist pattern on the substrate base plate, the first photoresist pattern including a first opening;

providing a second quantum dot solution;

coating the second quantum dot solution on one side of the first photoresist pattern far away from the substrate to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the first photoresist pattern and a part positioned in the first opening; and

and stripping the first photoresist pattern, removing the part of the second quantum dot light-emitting material layer covering the first photoresist pattern, and reserving the part of the second quantum dot light-emitting material layer in the first opening to form a second quantum dot light-emitting layer.

12. The method of fabricating a quantum dot light emitting structure according to claim 10, further comprising:

forming a second photoresist pattern on the substrate on which the second quantum dot light emitting layer is formed, the second photoresist pattern including a second opening;

providing a third quantum dot solution;

coating the third quantum dot solution on the substrate on which the second quantum dot light-emitting layer is formed to form a third quantum dot light-emitting material layer including a portion covering the second photoresist pattern and a portion located in the second opening; and

and stripping the second photoresist pattern, removing the part of the third quantum dot light-emitting material layer covering the second photoresist pattern, and reserving the part of the third quantum dot light-emitting material layer positioned in the second opening to form a third quantum dot light-emitting layer.

13. The method as claimed in claim 12, wherein the second quantum dot light-emitting layer is configured to emit light with wavelength ranging from 622-770 nm, and the third quantum dot light-emitting layer is configured to emit light with wavelength ranging from 492-577 nm.

14. The method of claim 12, wherein the second quantum dot solution comprises a second quantum dot with a surface modified with a second ligand, the third quantum dot solution comprises a third quantum dot with a surface modified with a third ligand, and the second ligand and the third ligand each comprise a photolytic chemical bond, the method further comprising:

illuminating the substrate on which the second quantum dot light emitting layer and the third quantum dot light emitting layer are formed, so that the photolytic chemical bonds in the second ligand and the third ligand are broken.

15. The method of claim 12, wherein stripping the first or second photoresist pattern comprises:

stripping the first photoresist pattern or the second photoresist pattern using at least one of an ultrasonic stripping process and a polar aprotic solvent boiling process.

16. The fabrication method of the quantum dot light-emitting structure according to any one of claims 1 to 4, wherein before forming the first quantum dot light-emitting material layer on the substrate base plate, the fabrication method further comprises:

forming a first sacrificial layer on a substrate;

forming a third photoresist pattern on one side of the first sacrificial layer, which is far away from the substrate base plate, wherein the third photoresist pattern comprises a third opening;

patterning the first sacrificial layer by taking the third photoresist pattern as a mask, and removing the part of the first sacrificial layer, which is positioned in the third opening;

providing a second quantum dot solution;

coating the second quantum dot solution on one side of the third photoresist pattern far away from the substrate to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the third photoresist pattern and a part positioned in the third opening; and

and stripping the third photoresist pattern and the first sacrificial layer, removing the part of the second quantum dot light-emitting material layer covering the third photoresist pattern, and reserving the part of the second quantum dot light-emitting material layer positioned in the third opening to form a second quantum dot light-emitting layer.

17. The method of fabricating a quantum dot light emitting structure according to claim 16, further comprising:

forming a second sacrificial layer on the substrate on which the second quantum dot light emitting layer is formed;

forming a fourth photoresist pattern on one side of the second sacrificial layer far away from the substrate base plate, wherein the fourth photoresist pattern comprises a fourth opening;

patterning the second sacrificial layer by taking the fourth photoresist pattern as a mask, and removing a part of the second sacrificial layer, which is positioned in the fourth opening;

providing a third quantum dot solution;

coating the third quantum dot solution on the substrate on which the second quantum dot light-emitting layer is formed to form a third quantum dot light-emitting material layer, wherein the third quantum dot light-emitting material layer comprises a portion covering the fourth photoresist pattern and a portion located in the fourth opening; and

and stripping the fourth photoresist pattern and the second sacrificial layer, removing the part of the third quantum dot light-emitting material layer covering the fourth photoresist pattern, and reserving the part of the third quantum dot light-emitting material layer positioned in the fourth opening to form a third quantum dot light-emitting layer.

18. A quantum dot light emitting structure comprising:

a substrate base plate;

the first quantum dot light-emitting layer is positioned on the substrate base plate; and

a second quantum dot light emitting layer on the substrate base plate,

wherein the ligand content of the first quantum dot light-emitting layer is less than 60% of the ligand content of the second quantum dot light-emitting layer.

19. The quantum dot light emitting structure of claim 18, wherein the first quantum dot light emitting layer comprises first quantum dots with a surface modified with a first ligand, first quantum dots without a surface modified with a ligand, and a photo-induced ligand removal agent.

20. The quantum dot light emitting structure of claim 19, wherein the photogenerator remover comprises a photoacid generator.

21. The quantum dot light emitting structure of claim 20, wherein the photoacid generator comprises at least one of a triazine-based compound, an iodonium-based compound, a sulfonium-based compound, and a perfluorobutyl-based compound.

22. The quantum dot light emitting structure of any one of claims 18-21, wherein the first quantum dot light emitting layer is configured to emit light with a wavelength range of 455-492 nm and the second quantum dot light emitting layer is configured to emit light with a wavelength range of 622-770 nm or with a wavelength range of 492-577 nm.

23. A display device comprising a quantum dot light emitting structure according to any of claims 18-22.

Technical Field

The embodiment of the disclosure relates to a quantum dot light-emitting structure, a manufacturing method thereof and a display device.

Background

An Active Matrix Organic Light Emitting Diode (AMOLED) display device is considered as a next generation display technology to replace a liquid crystal display device (LCD) due to advantages of a wide viewing angle, a high refresh rate, low power consumption, flexible display, and the like. With the continuous development of consumer market, the resolution of display devices is more and more demanded by consumers. The organic light emitting layer of an Active Matrix Organic Light Emitting Diode (AMOLED) display device is generally manufactured by an evaporation process or an inkjet printing process; due to the reasons of difficult alignment, insufficient control capability of an evaporation area and the like, the organic light-emitting layer formed by adopting the evaporation process is difficult to realize high resolution; the organic light emitting layer formed by the ink jet printing process also has difficulty in realizing high resolution. Therefore, the resolution of an Active Matrix Organic Light Emitting Diode (AMOLED) display device is relatively low, and it is difficult to compete with a liquid crystal display device (LCD).

On the other hand, with the continuous development of quantum dot light emitting diode (QLED) display technology, the quantum efficiency is continuously improved, and has substantially reached the level of industrialization. Therefore, the quantum dot light emitting diode (QLED) display technology has gradually become a hot point of research.

Disclosure of Invention

The embodiment of the disclosure provides a quantum dot light-emitting structure, a manufacturing method thereof and a display device. The manufacturing method of the quantum dot light-emitting structure can change the solubility of the first quantum dot light-emitting layer to be reserved through exposure, so that patterning of the first quantum dot light-emitting layer is achieved, and an ultrasonic stripping process or a more violent method such as polar aprotic solvent boiling is not needed, so that the complete appearance of the first quantum dot light-emitting layer can be ensured, and the light-emitting performance of the quantum dot light-emitting structure can be ensured.

At least one embodiment of the present disclosure provides a method for fabricating a quantum dot light emitting structure, including: providing a first quantum dot solution, wherein the first quantum dot solution comprises a first quantum dot with a surface modified with a first ligand and a photoinduced ligand remover, and the first ligand is dissolved in a first washing solvent; coating the first quantum dot solution on a substrate to form a first quantum dot luminescent material layer; partially exposing the first quantum dot light-emitting material layer such that the first quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photo-induced ligand removal agent configured to release a ligand removal agent under illumination to remove the first ligand in the exposed portions of the first quantum dot light-emitting material layer; and developing and washing the exposed first quantum dot luminescent material layer by adopting the first washing solvent to form a first quantum dot luminescent layer.

For example, in a method for fabricating a quantum dot light emitting structure provided in an embodiment of the present disclosure, the photoligand remover includes a photoacid generator.

For example, in the method for manufacturing a quantum dot light emitting structure according to an embodiment of the present disclosure, the photo-acid generator includes at least one of a triazine compound, an iodonium compound, a sulfonium compound, and a perfluorobutyl compound.

For example, in the method for manufacturing a quantum dot light emitting structure provided in an embodiment of the present disclosure, in the first quantum dot solution, a mass percentage ratio of the photogenerated ligand remover to the first quantum dots with the surface modified with the first ligands is in a range of 4% to 6%.

For example, in a method for manufacturing a quantum dot light emitting structure according to an embodiment of the present disclosure, the first rinsing solvent includes at least one of toluene, xylene, chlorobenzene, and other aromatic hydrocarbons.

For example, in a method for manufacturing a quantum dot light emitting structure provided in an embodiment of the present disclosure, partially exposing the first quantum dot light emitting material layer includes: partially exposing the first quantum dot light-emitting material layer with ultraviolet light having energy of 90-500mJ/cm to form the exposed portion and the unexposed portion²Within the range of (a).

For example, the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure further includes: and annealing the substrate base plate formed with the first quantum dot light-emitting layer, wherein the annealing temperature is in the range of 80-180 ℃, and the annealing time is in the range of 5-30 minutes. For example, in the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure, the first quantum dot light emitting layer is configured to emit light with a wavelength range of 455-492 nm.

For example, the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure further includes: providing a second quantum dot solution, wherein the second quantum dot solution comprises a second quantum dot with a surface modified with a second ligand and a photoinduced ligand remover, and the second ligand is dissolved in a second washing solvent; coating the second quantum dot solution on the substrate with the first quantum dot light-emitting layer to form a second quantum dot light-emitting material layer; partially exposing the second quantum dot light-emitting material layer such that the second quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photo-induced ligand removal agent configured to release a ligand removal agent under illumination to remove the second ligand in the exposed portions of the second quantum dot light-emitting material layer; and developing and washing the exposed second quantum dot luminescent material layer by using the second washing solvent to form a second quantum dot luminescent layer.

For example, in a method for manufacturing a quantum dot light emitting structure provided by an embodiment of the present disclosure, the second ligand and the first ligand are made of the same material, and the second rinsing solvent and the first rinsing solvent are made of the same material.

For example, in a manufacturing method of a quantum dot light emitting structure provided in an embodiment of the present disclosure, before forming the first quantum dot light emitting material layer on the substrate base plate, the manufacturing method further includes: forming a first photoresist pattern on the substrate base plate, the first photoresist pattern including a first opening; providing a second quantum dot solution; coating the second quantum dot solution on one side of the first photoresist pattern far away from the substrate to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the first photoresist pattern and a part positioned in the first opening; and stripping the first photoresist pattern, removing the part of the second quantum dot light-emitting material layer covering the first photoresist pattern, and reserving the part of the second quantum dot light-emitting material layer in the first opening to form a second quantum dot light-emitting layer.

For example, the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure further includes: forming a second photoresist pattern on the substrate on which the second quantum dot light emitting layer is formed, the second photoresist pattern including a second opening; providing a third quantum dot solution; coating the third quantum dot solution on the substrate on which the second quantum dot light-emitting layer is formed to form a third quantum dot light-emitting material layer including a portion covering the second photoresist pattern and a portion located in the second opening; and stripping the second photoresist pattern, wherein the part of the third quantum dot light-emitting material layer covering the second photoresist pattern is removed, and the part of the third quantum dot light-emitting material layer positioned in the second opening is reserved and forms a third quantum dot light-emitting layer.

For example, in the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure, the second quantum dot light emitting layer is configured to emit light with a wavelength range of 622-770 nm, and the third quantum dot light emitting layer is configured to emit light with a wavelength range of 492-577 nm.

For example, in a manufacturing method of a quantum dot light emitting structure provided in an embodiment of the present disclosure, the second quantum dot solution includes a second quantum dot with a surface modified with a second ligand, the third quantum dot solution includes a third quantum dot with a surface modified with a third ligand, and both the second ligand and the third ligand include photolytic chemical bonds, and the manufacturing method further includes: illuminating the substrate on which the second quantum dot light emitting layer and the third quantum dot light emitting layer are formed, so that the photolytic chemical bonds in the second ligand and the third ligand are broken.

For example, in a method for manufacturing a quantum dot light emitting structure provided in an embodiment of the present disclosure, stripping the first photoresist pattern or the second photoresist pattern includes: stripping the first photoresist pattern or the second photoresist pattern using at least one of an ultrasonic stripping process and a polar aprotic solvent boiling process.

For example, in a manufacturing method of a quantum dot light emitting structure provided in an embodiment of the present disclosure, before forming the first quantum dot light emitting material layer on the substrate base plate, the manufacturing method further includes: forming a first sacrificial layer on the substrate base plate; forming a third photoresist pattern on one side of the first sacrificial layer, which is far away from the substrate base plate, wherein the third photoresist pattern comprises a third opening; patterning the first sacrificial layer by taking the third photoresist pattern as a mask, and removing the part of the first sacrificial layer, which is positioned in the third opening; providing a second quantum dot solution; coating the second quantum dot solution on one side of the third photoresist pattern far away from the substrate to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the third photoresist pattern and a part positioned in the third opening; and stripping the third photoresist pattern and the first sacrificial layer, wherein the part of the second quantum dot light-emitting material layer covering the third photoresist pattern is removed, and the part of the second quantum dot light-emitting material layer positioned in the third opening is reserved and forms a second quantum dot light-emitting layer.

For example, the method for manufacturing the quantum dot light emitting structure provided by an embodiment of the present disclosure further includes: forming a second sacrificial layer on the substrate on which the second quantum dot light emitting layer is formed; forming a fourth photoresist pattern on one side of the second sacrificial layer far away from the substrate base plate, wherein the fourth photoresist pattern comprises a fourth opening; patterning the second sacrificial layer by taking the fourth photoresist pattern as a mask, and removing a part of the second sacrificial layer, which is positioned in the fourth opening; providing a third quantum dot solution; coating the third quantum dot solution on the substrate on which the second quantum dot light-emitting layer is formed to form a third quantum dot light-emitting material layer, wherein the third quantum dot light-emitting material layer comprises a portion covering the fourth photoresist pattern and a portion located in the fourth opening; and stripping the fourth photoresist pattern and the second sacrificial layer, wherein the part of the third quantum dot light-emitting material layer covering the fourth photoresist pattern is removed, and the part of the third quantum dot light-emitting material layer positioned in the fourth opening is reserved and forms a third quantum dot light-emitting layer.

At least one embodiment of the present disclosure also provides a quantum dot light emitting structure, including: a substrate base plate; the first quantum dot light-emitting layer is positioned on the substrate base plate; and the second quantum dot light-emitting layer is positioned on the substrate base plate, and the content of the ligand of the first quantum dot light-emitting layer is less than 60% of that of the ligand of the second quantum dot light-emitting layer.

For example, in a quantum dot light emitting structure provided by an embodiment of the present disclosure, the first quantum dot light emitting layer includes a first quantum dot with a surface modified with a first ligand, a first quantum dot with a surface not modified with a ligand, and a photo-induced ligand remover.

For example, in a quantum dot light emitting structure provided by an embodiment of the present disclosure, the photoligand remover includes a photoacid generator.

For example, in the quantum dot light emitting structure provided in an embodiment of the present disclosure, the photo-acid generator includes at least one of a triazine compound, an iodonium compound, a sulfonium compound, and a perfluorobutyl compound.

For example, in the quantum dot light emitting structure provided by an embodiment of the present disclosure, the first quantum dot light emitting layer is configured to emit light with a wavelength range of 455-492 nm, and the second quantum dot light emitting layer is configured to emit light with a wavelength range of 522-770 nm or light with a wavelength range of 492-577 nm.

At least one embodiment of the present disclosure further provides a display device, including any one of the quantum dot light-emitting structures described above.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1 is a flowchart illustrating a method for fabricating a quantum dot light-emitting structure according to an embodiment of the present disclosure;

FIGS. 2A-2C are schematic diagrams illustrating steps of a method for fabricating a quantum dot light-emitting structure according to an embodiment of the present disclosure;

FIGS. 3A-3F are schematic diagrams illustrating steps of a method for fabricating a quantum dot light-emitting structure according to an embodiment of the present disclosure;

fig. 4A-4J are schematic step-by-step diagrams illustrating another method for fabricating a quantum dot light-emitting structure according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a quantum dot light-emitting structure according to an embodiment of the present disclosure; and

fig. 6 is a schematic diagram of a display device according to an embodiment of the disclosure.

Detailed Description

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

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.

The quantum dot light emitting diode (QLED) display technology may utilize a photoresist stripping process (lift-off) or a lift-off like process to pattern the quantum dot light emitting layer. However, in the process of stripping the photoresist, a relatively severe method such as an ultrasonic stripping process or polar aprotic solvent boiling is often required, and the relatively severe methods are easy to damage the morphology of the prepared functional film layer, so that the luminescence performance of the finally formed quantum dot luminescence structure is affected. Moreover, the blue light quantum dots have wider band gaps and are weaker in stability than the red and green light quantum dots, so that the blue light quantum dots are poorer in tolerance to a glue stripping process in patterning and are easily damaged, and accordingly, the blue light in a full-color quantum dot light-emitting diode (QLED) display device is lower in brightness and cannot achieve a full-color display effect.

In view of the above, the present disclosure provides a quantum dot light emitting structure, a method for manufacturing the quantum dot light emitting structure, and a display device. The manufacturing method of the quantum dot light-emitting structure comprises the following steps: providing a first quantum dot solution, wherein the first quantum dot solution comprises a first quantum dot with a surface modified with a first ligand and a photoinduced ligand remover, and the first ligand is dissolved in a first washing solvent; coating the first quantum dot solution on a substrate to form a first quantum dot luminescent material layer; partially exposing the first quantum dot light-emitting material layer such that the first quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photobase removing agent being configured to release the ligand removing agent under illumination to remove the first ligands in the portions of the first quantum dot light-emitting material layer including the exposed portions; and developing and washing the exposed first quantum dot luminescent material layer by adopting a first washing solvent to form a first quantum dot luminescent layer. Therefore, the manufacturing method of the quantum dot light-emitting structure can realize patterning of the first quantum dot light-emitting layer, and a more violent method such as an ultrasonic stripping process or polar aprotic solvent boiling is not needed, so that the complete appearance of the first quantum dot light-emitting layer can be ensured, and the light-emitting performance of the quantum dot light-emitting structure can be further ensured.

The following describes a quantum dot light-emitting structure, a method for manufacturing the same, and a display device in detail with reference to the accompanying drawings.

An embodiment of the disclosure provides a method for manufacturing a quantum dot light-emitting structure. Fig. 1 is a flowchart illustrating a method for fabricating a quantum dot light-emitting structure according to an embodiment of the present disclosure; fig. 2A-2C are schematic step-by-step diagrams illustrating a method for fabricating a quantum dot light-emitting structure according to an embodiment of the disclosure.

As shown in fig. 1, the method for fabricating the quantum dot light emitting structure includes the following steps S101 to S104.

Step S101: providing a first quantum dot solution, wherein the first quantum dot solution comprises a first quantum dot with a surface modified with a first ligand and a photoinduced ligand remover, and the first ligand is dissolved in a first washing solvent.

Step S102: and coating the first quantum dot solution on the substrate base plate to form a first quantum dot luminescent material layer.

As shown in fig. 2A, a first quantum dot solution may be coated on the substrate base 150 by a spin coating process to form a first quantum dot light emitting material layer 110; the spin coating process may be performed at 2000-3000 rpm. For example 2500 rpm. Of course, the embodiments of the present disclosure include, but are not limited to, the first quantum dot solution may be coated on the substrate base plate by other suitable methods.

Step S103: and partially exposing the first quantum dot light-emitting material layer so that the first quantum dot light-emitting material layer comprises exposed parts and unexposed parts, wherein the photoinduced ligand remover is configured to release the ligand remover under illumination so as to remove the first ligands of the exposed parts of the first quantum dot light-emitting material layer.

As shown in fig. 2B, the first quantum dot light-emitting material layer 110 may be partially exposed directly by an exposure machine such that the first quantum dot light-emitting material layer 110 includes an exposed portion 112 and an unexposed portion 114, and the first ligands of the exposed portion 112 of the first quantum dot light-emitting material layer 110 are removed.

Step S104: developing and washing the exposed first quantum dot luminescent material layer by using a first washing solvent, wherein the unexposed part of the first quantum dot luminescent material layer is dissolved and removed by the first washing solvent; the exposed part of the first quantum dot light-emitting material layer is insoluble in the first washing solvent and forms a first quantum dot light-emitting layer.

As shown in fig. 2C, developing and developing the exposed first quantum dot luminescent material layer 110 by using a first developing solvent; since the first ligand is dissolved in the first developing solvent, the unexposed portion 114 of the first quantum dot luminescent material layer 110 is dissolved and removed by the first developing solvent, and the exposed portion 112 of the first quantum dot luminescent material layer 110 is not dissolved in the first developing solvent, and thus remains on the substrate base 150. The exposed portion 112 of the first quantum dot light-emitting material layer 110 is the first quantum dot light-emitting layer 112.

In the method for manufacturing a quantum dot light-emitting structure provided by the embodiment of the disclosure, the light-induced ligand remover is used for releasing the ligand remover under illumination through an exposure process, so as to remove the first ligand of the exposed part of the first quantum dot light-emitting material layer, so that the exposed part of the first quantum dot light-emitting material layer is insoluble in the first rinsing solvent, and thus the first quantum dot light-emitting layer is retained and formed on the substrate, and the unexposed part of the first quantum dot light-emitting material layer is dissolved and removed by the first rinsing solvent. Therefore, the manufacturing method of the quantum dot light-emitting structure can realize patterning of the first quantum dot light-emitting layer, and a more violent method such as an ultrasonic stripping process or polar aprotic solvent boiling is not needed, so that the complete appearance of the first quantum dot light-emitting layer can be ensured, and the light-emitting performance of the quantum dot light-emitting structure can be further ensured. In addition, the first quantum dot light-emitting layer can be directly patterned through an exposure process, so that the first quantum dot light-emitting layer has high precision and small size, and the resolution of the prepared quantum dot light-emitting structure is improved.

In some examples, the photoligand remover may include a photoacid generator. The photoacid generator generates hydrogen ions after being irradiated with light, and the hydrogen ions are combined with the first ligands, thereby removing the first ligands from the exposed portions of the first quantum dot light-emitting material layer. On the other hand, the photoacid generator is used to remove the first ligand, so that the influence on the luminous efficiency of the first quantum dot can be avoided. Of course, the embodiments of the present disclosure include, but are not limited to, the photo-induced ligand removal agent may also be other materials that can remove the first ligand from the first quantum dot.

For example, the photoacid generator includes at least one of a triazine-based compound, an iodonium-based compound, a sulfonium-based compound, and a perfluorobutyl-based compound.

In some examples, the ratio of the mass percent of the photogenerated ligand removal agent to the first quantum dots surface-modified with the first ligand in the first quantum dot solution is in a range of 4% to 6%. For example, the ratio of the mass percentage of the photogenerated ligand remover to the first quantum dots with the surface modified with the first ligand is 5%. Therefore, the photoinduced ligand remover can well remove the first ligand of the exposed part of the first quantum dot luminescent material layer, and meanwhile, the luminous efficiency of the first quantum dot luminescent layer formed by the first quantum dot solution is ensured.

In some examples, the first flush solvent includes at least one of hexane, octane, toluene, xylene, chlorobenzene, and like aromatic hydrocarbons. The first ligand may include oleic acid, oleylamine, octanethiol, dodecanethiol, and the like. It is noted that the first rinsing solvent may be the same as the solvent in the first quantum dot solution. Of course, the first rinsing solvent may also be different from the solvent in the first quantum dot solution. In some examples, partially exposing the first quantum dot light-emitting material layer includes: partially exposing the first quantum dot luminescent material layer by ultraviolet light with energy of 90-500mJ/cm²Within a range of, for example, 100mJ/cm². Thus, the exposure process is effective to cause the photoligand remover to release the ligand remover upon exposure to light.

In some examples, the method for fabricating the quantum dot light emitting structure further includes: and annealing the substrate base plate with the first quantum dot light-emitting layer, wherein the annealing temperature is in the range of 80-180 ℃, and the annealing time is in the range of 5-30 minutes. Therefore, the first quantum dot light-emitting layer formed by the manufacturing method of the quantum dot light-emitting structure has better stability and luminous efficiency.

In some examples, the first quantum dot light emitting layer is configured to emit blue light, e.g., light having a wavelength range of 455-492 nanometers. The quantum dot emitting blue light has wider band gap and weaker stability than red and green light quantum dots, so the manufacturing method of the quantum dot light-emitting structure can realize patterning of the first quantum dot light-emitting layer through the photoinduced ligand remover, the exposure process and the washing process without using an ultrasonic stripping process or a more violent method such as polar aprotic solvent boiling and the like, thereby ensuring the complete appearance of the first quantum dot light-emitting layer and further ensuring the light-emitting performance of the quantum dot light-emitting structure.

It should be noted that the substrate may include other quantum dot light emitting layers that have been prepared, such as a red light emitting quantum dot light emitting layer and a green light emitting quantum dot light emitting layer. In this case, although a small amount of first quantum dots emitting blue light may remain on the quantum dot light-emitting layer emitting red light and the quantum dot light-emitting layer emitting green light in the process of forming the first quantum dot light-emitting layer emitting blue light using the above-described method, there is no problem of spectral color mixing because there is forster energy transfer between the first quantum dots emitting blue light and the quantum dots emitting red light or filtered light.

For example, the first quantum dot may be a CdSe/ZnS quantum dot. Of course, embodiments of the present disclosure include, but are not limited to, other cadmium-containing quantum dot materials, such as CdSe/ZnSe, CdS, CdSe, or CdS/ZnS; of course, the first quantum dots can also be cadmium-free quantum dots, such as InP/ZnSe, InP/ZnSe/ZnS, ZnSe, InP, PbS, CsPbCl₃、CsPbBr₃、CsPhI₃、ZnSe、InP/ZnS、PbS/ZnS、CsPbCl₃/ZnS、CsPbBr₃(ii) ZnS, or CsPhI₃/ZnS。

For example, the first quantum dot may employ a core-shell structure. Therefore, the first quantum dots can have a core-shell structure, so that the core is protected, and the surface defects can be passivated better by using a shell material matched with the lattice constant of the core material.

In some examples, the method of making further comprises: providing a second quantum dot solution, wherein the second quantum dot solution comprises a second quantum dot with a surface modified with a second ligand and a photoinduced ligand remover, and the second ligand is dissolved in a second washing solvent; coating the second quantum dot solution on the substrate with the first quantum dot light-emitting layer to form a second quantum dot light-emitting material layer; partially exposing the second quantum dot light-emitting material layer such that the second quantum dot light-emitting material layer includes exposed portions and unexposed portions, the photobase removing agent being configured to release the ligand removing agent under illumination to remove the second ligands in the exposed portions of the second quantum dot light-emitting material layer; and developing and washing the exposed second quantum dot luminescent material layer by adopting a second washing solvent, dissolving and removing the unexposed part of the second quantum dot luminescent material layer by using the second washing solvent, and insolubilizing the exposed part of the second quantum dot luminescent material layer in the second washing solvent to form a second quantum dot luminescent layer. Therefore, the manufacturing method can also utilize an exposure process and a photoinduced ligand remover to pattern the second quantum dot light-emitting layer, and does not need an ultrasonic stripping process or a more violent method such as polar aprotic solvent boiling and the like, so that the complete appearance of the second quantum dot light-emitting layer can be ensured, and the light-emitting performance of the quantum dot light-emitting structure can be further ensured. In addition, the second quantum dot light-emitting layer can be directly patterned through an exposure process, so that the second quantum dot light-emitting layer has high precision and small size, and the resolution of the prepared quantum dot light-emitting structure is improved.

It should be noted that, when the quantum dot light-emitting structure further includes a third quantum dot light-emitting layer, the manufacturing method may further use an exposure process and a photoligand remover to pattern the third quantum dot light-emitting layer, which is not described herein again.

For example, the first quantum dot light emitting layer is a quantum dot light emitting layer emitting blue light (e.g., light with a wavelength range of 455-492 nm), and the second quantum dot light emitting layer is a quantum dot light emitting layer emitting red light (e.g., light with a wavelength range of 622-770 nm) or green light (e.g., light with a wavelength range of 492-577 nm).

In some examples, the second ligand is the same material as the first ligand and the second flush solvent is the same material as the first flush solvent. In some examples, before forming the first quantum dot light emitting material layer on the substrate, the method for manufacturing the quantum dot light emitting structure further includes: forming a first photoresist pattern on a substrate base plate, the first photoresist pattern including a first opening; providing a second quantum dot solution; coating a second quantum dot solution on one side, far away from the substrate base plate, of the first photoresist pattern to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the first photoresist pattern and a part located in the first opening; and stripping the first photoresist pattern, removing the part of the second quantum dot light-emitting material layer covering the first photoresist pattern, and reserving the part of the second quantum dot light-emitting material layer positioned in the first opening to form a second quantum dot light-emitting layer. Therefore, the manufacturing method can utilize the photoresist to carry out lift-off process (lift-off) to pattern the second quantum dot light-emitting layer.

Fig. 3A to fig. 3F are schematic step-by-step diagrams illustrating a method for fabricating a quantum dot light emitting structure according to an embodiment of the disclosure.

As shown in fig. 3A, a first photoresist pattern 161 is formed on the substrate base plate 150, the first photoresist pattern 161 including a first opening 1610.

For example, the substrate may be a transparent substrate such as a glass substrate, a plastic substrate, or a quartz substrate; the first photoresist pattern may be a negative photoresist material. In addition, the first photoresist pattern may be prepared by coating a photoresist material layer, and then performing exposure and development.

For example, the photoresist material may be coated on the base substrate 150 through a spin coating process at a rotation speed of about 4000rpm, and the formed photoresist material is exposed through an exposure process at an energy of about 35mJ/cm2, and then the exposed photoresist material is developed using a solvent such as xylene, thereby forming the first photoresist pattern. The developing process described above lasted approximately 90 seconds.

As shown in fig. 3B, a second quantum dot solution is provided, and the second quantum dot solution is coated on a side of the first photoresist pattern far from the substrate to form a second quantum dot light emitting material layer 120, wherein the second quantum dot light emitting material layer 120 includes a portion 124 covering the first photoresist pattern and a portion 122 located in the first opening 1610.

For example, a spin coating process may be used to coat a 15mg/ml second quantum dot solution on a side of the first photoresist pattern away from the substrate to form a second quantum dot light-emitting material layer; the spin coating process described above was carried out at a speed of about 2500 rpm.

As shown in fig. 3C, the first photoresist pattern 161 is stripped, a portion 124 of the second quantum dot light emitting material layer 120 covering the first photoresist pattern 161 is removed, and a portion 122 of the second quantum dot light emitting material layer 120 located in the first opening 161 is remained and forms the second quantum dot light emitting layer 122.

In the manufacturing method of the quantum dot light-emitting structure, the first photoresist pattern can be stripped by adopting at least one of an ultrasonic stripping process and a polar aprotic solvent boiling process, when the first photoresist pattern is stripped, the second quantum dot light-emitting material layer formed on the first photoresist pattern is stripped together, and the part of the second quantum dot light-emitting material layer positioned in the first opening is remained on the substrate base plate, so that the patterning of the second quantum dot light-emitting layer is realized.

For example, the power of the ultrasonic wave in the ultrasonic peeling process is about 30W, and the duration is about 90 seconds.

For example, the second quantum dot light emitting layer may be a quantum dot light emitting layer with higher stability, such as a red light emitting quantum dot light emitting layer.

In some examples, the method for fabricating the quantum dot light emitting structure further includes: forming a second photoresist pattern on the substrate on which the second quantum dot light emitting layer is formed, the second photoresist pattern including a second opening; providing a third quantum dot solution; coating a third quantum dot solution on the substrate on which the second quantum dot light-emitting layer is formed to form a third quantum dot light-emitting material layer, wherein the third quantum dot light-emitting material layer comprises a part covering the second photoresist pattern and a part located in the second opening; and stripping the second photoresist pattern, removing the part of the third quantum dot light-emitting material layer covering the second photoresist pattern, reserving the part of the third quantum dot light-emitting material layer positioned in the second opening and forming a third quantum dot light-emitting layer, wherein the substrate base plate formed with the second quantum dot light-emitting layer and the third quantum dot light-emitting layer is the substrate base plate. Therefore, the manufacturing method can utilize the photoresist to carry out a lift-off process (lift-off) to pattern the third quantum dot light-emitting layer.

As shown in fig. 3D, a second photoresist pattern 162 is formed on the substrate base plate 150 where the second quantum dot light emitting layer 112 is formed, and the second photoresist pattern 162 includes a second opening 1620.

Similarly, the second photoresist pattern may be a negative photoresist material. In addition, the second photoresist pattern may also be prepared by coating a photoresist material layer, and then performing exposure and development. Specific parameters of the coating, exposing and developing processes can be referred to the description of the first photoresist pattern, and are not described herein again.

As shown in fig. 3E, a third quantum dot solution is provided, and the third quantum dot solution is coated on the substrate base plate 150 on which the second quantum dot light emitting layer 122 is formed to form a third quantum dot light emitting material layer 130, and the third quantum dot light emitting material layer 130 includes a portion 134 covering the second photoresist pattern 162 and a portion 132 located in the second opening 1620.

Similarly, a third quantum dot solution of 15mg/ml can be coated on one side of the second photoresist pattern far away from the substrate by adopting a spin coating process to form a third quantum dot light-emitting material layer; the spin coating process described above was carried out at a speed of about 2500 rpm.

As shown in fig. 3F, the second photoresist pattern 162 is stripped, a portion 134 of the third quantum dot light-emitting material layer 130 covering the second photoresist pattern 162 is removed, and a portion 132 of the third quantum dot light-emitting material layer 130 in the second opening 1620 is remained and forms the third quantum dot light-emitting layer 132.

For example, the second photoresist pattern may also be stripped using at least one of an ultrasonic stripping process and a polar aprotic solvent boiling process, and when the second photoresist pattern is stripped, the third quantum dot light-emitting material layer formed on the second photoresist pattern is also stripped together, and a portion of the third quantum dot light-emitting material layer located in the second opening is left on the substrate base substrate, thereby achieving patterning of the third quantum dot light-emitting layer.

For example, the third quantum dot light emitting layer may be a quantum dot light emitting layer with high stability, such as a quantum dot light emitting layer emitting green light. Therefore, the quantum dot light-emitting structure prepared by the manufacturing method of the quantum dot light-emitting structure can realize full-color display.

In some examples, the second quantum dot solution includes a second quantum dot with a surface modified with a second ligand, the third quantum dot solution includes a third quantum dot with a surface modified with a third ligand, the second ligand and the third ligand each include a photolytic chemical bond, and the method for fabricating the quantum dot light emitting structure further includes: and (3) irradiating the substrate formed with the second quantum dot light-emitting layer and the third quantum dot light-emitting layer by light to break the photolytic chemical bonds in the second ligand and the third ligand and change the long-chain structure of the second ligand into the short-chain structure, so that the second quantum dot light-emitting layer and the third quantum dot light-emitting layer are insoluble in the first washing solvent. Therefore, the manufacturing method of the quantum dot light-emitting structure can avoid the adverse effect of the subsequent washing process on the second quantum dot light-emitting layer and the third quantum dot light-emitting layer.

In some examples, the second quantum dot and the third quantum dot may both be CdSe/ZnS quantum dots. Of course, the embodiments of the present disclosure include, but are not limited to, the second quantum dot and the third quantum dot may also be quantum dots of other materials, and reference may be made to the description of the first quantum dot.

In some examples, before forming the first quantum dot light emitting material layer on the substrate base plate, the manufacturing method further includes: forming a first sacrificial layer on a substrate; forming a third photoresist pattern on one side of the first sacrificial layer, which is far away from the substrate base plate, wherein the third photoresist pattern comprises a third opening; patterning the first sacrificial layer by taking the third photoresist pattern as a mask, and removing the part of the first sacrificial layer, which is positioned in the third opening; providing a second quantum dot solution; coating a second quantum dot solution on one side, far away from the substrate base plate, of the third photoresist pattern to form a second quantum dot light-emitting material layer, wherein the second quantum dot light-emitting material layer comprises a part covering the third photoresist pattern and a part located in the third opening; and stripping the third photoresist pattern and the first sacrificial layer, removing the part of the second quantum dot light-emitting material layer covering the third photoresist pattern, and reserving the part of the second quantum dot light-emitting material layer positioned in the third opening to form a second quantum dot light-emitting layer.

It should be noted that the photoresist may still have a certain residue on the substrate due to the lift-off process. Therefore, the method for manufacturing the quantum dot light-emitting structure provided by the embodiment of the disclosure is not limited to the above-mentioned lift-off process (lift-off) directly using the photoresist, and a sacrificial layer may be formed on one side of the photoresist pattern close to the substrate to improve the lift-off effect.

Fig. 4A to fig. 4J are schematic step-by-step diagrams of another method for manufacturing a quantum dot light emitting structure according to an embodiment of the disclosure.

As shown in fig. 4A, before forming the first quantum dot light-emitting material layer on the substrate, the method for manufacturing the quantum dot light-emitting structure further includes: a first sacrificial layer 171 is formed on the base substrate 150.

For example, the material of the first sacrificial layer may use an alcohol-soluble polymer, such as polyvinylpyrrolidone.

For example, a 30mg/ml polyvinylpyrrolidone solution may be coated on the substrate base plate 150 by a spin coating process and left for about 5 minutes to form the first sacrificial layer, and the rotation speed of the spin coating process may be within the range of 1200 rpm and 1700rpm, such as 1500 rpm.

As shown in fig. 4B, a third photoresist pattern 163 is formed on a side of the first sacrificial layer 171 away from the substrate base plate 150, and the third photoresist pattern 163 includes a third opening 1630.

Similarly, the third photoresist pattern may use a negative photoresist material. In addition, the third photoresist pattern may also be prepared by coating a photoresist material layer, and then performing exposure and development. Specific parameters of the coating, exposing and developing processes can be referred to the description of the first photoresist pattern, and are not described herein again.

As shown in fig. 4C, the first sacrificial layer 171 is patterned by using the third photoresist pattern 1630 as a mask, and a portion of the first sacrificial layer 171 located in the third opening 1630 is removed, so that the first sacrificial layer 171 has the same pattern as the third photoresist pattern 1630.

For example, a portion of first sacrificial layer 171 located in third opening 1630 may be removed by an etching process.

As shown in fig. 4D, a second quantum dot solution is provided, and the second quantum dot solution is coated on a side of the third photoresist pattern 163 away from the substrate base plate 150 to form a second quantum dot luminescent material layer 120, wherein the second quantum dot luminescent material layer 120 includes a portion 124 covering the third photoresist pattern 163 and a portion 122 located in the third opening 1630.

As shown in fig. 4E, the third photoresist pattern 163 and the first sacrificial layer 171 are stripped, a portion 124 of the second quantum dot light emitting material layer 120 covering the third photoresist pattern 163 is removed, and a portion 122 of the second quantum dot light emitting material layer 120 located in the third opening 1630 is remained and forms the second quantum dot light emitting layer 122.

In the manufacturing method of the quantum dot light-emitting structure, the first sacrificial layer can be stripped by adopting an ultrasonic stripping process, when the first sacrificial layer is stripped, the third photoresist pattern formed on the first sacrificial layer and the second quantum dot light-emitting material layer are stripped together, and the part of the second quantum dot light-emitting material layer positioned in the third opening is remained on the substrate base plate, so that the patterning of the second quantum dot light-emitting layer is realized. In addition, the residue cannot be formed on the substrate in the stripping process of the sacrificial layer, so that the product yield and the performance of the quantum dot light-emitting structure can be improved.

As shown in fig. 4F, the method for manufacturing the quantum dot light emitting structure further includes: a second sacrificial layer 172 is formed on the base substrate 150 where the second quantum dot light emitting layer 122 is formed.

For example, the material of the second sacrificial layer may use an alcohol-soluble polymer, such as polyvinylpyrrolidone. It should be noted that the second sacrificial layer and the first sacrificial layer may be made of the same material or different materials.

As shown in fig. 4G, a fourth photoresist pattern 164 is formed on a side of the second sacrificial layer 172 away from the substrate base 150, and the fourth photoresist pattern 164 includes a fourth opening 1640.

Similarly, the fourth photoresist pattern may use a negative photoresist material. In addition, the fourth photoresist pattern may also be prepared by coating a photoresist material layer, and then performing exposure and development. Specific parameters of the coating, exposing and developing processes can be referred to the description of the first photoresist pattern, and are not described herein again.

As shown in fig. 4H, the second sacrificial layer 172 is patterned by using the fourth photoresist pattern 1640 as a mask, and a portion of the second sacrificial layer 172 located at the fourth opening 1640 is removed.

As shown in fig. 4I, a third quantum dot solution is provided, and the third quantum dot solution is coated on the substrate 150 on which the second quantum dot light emitting layer 122 is formed to form a third quantum dot light emitting material layer 130, the third quantum dot light emitting material layer 130 including a portion 134 covering the fourth photoresist pattern 164 and a portion 132 located in the fourth opening 1640.

As shown in fig. 4J, and the fourth photoresist pattern 164 and the second sacrificial layer 172 are stripped, a portion of the third quantum dot light emitting material layer 130 covering the fourth photoresist pattern 164 is removed, a portion 132 of the third quantum dot light emitting material layer 130 located in the fourth opening 1640 is remained and forms the third quantum dot light emitting layer 132, and the base substrate 150 formed with the second quantum dot light emitting layer 122 and the third quantum dot light emitting layer 132 is the base substrate 150.

In the manufacturing method of the quantum dot light-emitting structure, the second sacrificial layer can be stripped by adopting an ultrasonic stripping process, when the second sacrificial layer is stripped, a fourth photoresist pattern formed on the second sacrificial layer and the third quantum dot light-emitting material layer are stripped together, and the part of the third quantum dot light-emitting material layer positioned in the fourth opening is remained on the substrate base plate, so that the patterning of the third quantum dot light-emitting layer is realized. In addition, the residue cannot be formed on the substrate in the stripping process of the sacrificial layer, so that the product yield and the performance of the quantum dot light-emitting structure can be improved.

Similarly, in the above method for fabricating a quantum dot light-emitting structure using a sacrificial layer, the second quantum dot solution includes a second quantum dot with a surface modified with a second ligand, the third quantum dot solution includes a third quantum dot with a surface modified with a third ligand, and both the second ligand and the third ligand include photolytic chemical bonds, and the method further includes: and (3) irradiating the substrate formed with the second quantum dot light-emitting layer and the third quantum dot light-emitting layer by light to break the photolytic chemical bonds in the second ligand and the third ligand and change the long-chain structure of the second ligand into the short-chain structure, so that the second quantum dot light-emitting layer and the third quantum dot light-emitting layer are insoluble in the first washing solvent. Therefore, the manufacturing method of the quantum dot light-emitting structure can avoid the adverse effect of the subsequent washing process on the second quantum dot light-emitting layer and the third quantum dot light-emitting layer. For example, the materials of the second ligand and the third ligand may be amine-based ligand, carboxyl-based ligand, mercapto-based ligand, etc.; the photolytic chemical bonds include peroxy bonds, peroxy sulfur bonds, azo bonds, and the like.

It should be noted that the manufacturing method of the quantum dot light emitting structure provided in the embodiment of the present disclosure is not limited to the above photoresist stripping process (lift-off) to implement the patterning of the second quantum dot light emitting layer and the third quantum dot light emitting layer, and the above photogenerator remover, exposure process, and rinsing process may also be used to implement the patterning of the second quantum dot light emitting layer and the third quantum dot light emitting layer, that is, the first quantum dot light emitting layer, the second quantum dot light emitting layer, and the third quantum dot light emitting layer are all prepared by the above photogenerator remover, exposure process, and rinsing process.

In some examples, before forming the first sacrificial layer or the first photoresist pattern on the substrate base plate, the method for fabricating the quantum dot light emitting structure further includes: a first electrode and an electron transport layer are sequentially formed on a base substrate. For example, the material of the first electrode may be a conductive metal oxide, such as Indium Tin Oxide (ITO). The material of the electron transport layer may be zinc oxide (ZnO).

For example, the zinc oxide thin film may be formed using a deposition process or a sputtering process.

In some examples, after forming the first quantum dot light emitting layer on the substrate base plate, the method for manufacturing the quantum dot light emitting structure further includes: a hole transport layer and a second electrode are sequentially formed on the substrate on which the first quantum dot light emitting layer is formed, and the material of the second electrode may be a metal, such as silver. In this case, the first electrode is a cathode and the second electrode is an anode. Of course, embodiments of the present disclosure include, but are not limited to, the first electrode may also be a cathode, and the second electrode may also be an anode; other structures of the quantum dot light emitting structure may adopt a general design.

In some examples, the method for fabricating the quantum dot light emitting structure further includes: and annealing the substrate base plate formed with the second quantum dot light-emitting layer and the third quantum dot light-emitting layer, wherein the annealing temperature is in the range of 80-180 ℃, for example 120 ℃, and the annealing time is in the range of 5-30 minutes, for example 20 minutes. Therefore, the second quantum dot light-emitting layer and the third quantum dot light-emitting layer formed by the manufacturing method of the quantum dot light-emitting structure have better stability and luminous efficiency.

An embodiment of the present disclosure further provides a quantum dot light emitting structure. Fig. 5 is a schematic structural diagram of a quantum dot light-emitting structure according to an embodiment of the present disclosure. As shown in fig. 5, the quantum dot light-emitting structure is a quantum dot light-emitting structure manufactured by any one of the above-described methods for manufacturing a quantum dot light-emitting structure. Therefore, the quantum dot light-emitting structure can ensure that the first quantum dot light-emitting layer is complete in shape, and further can ensure the light-emitting performance of the quantum dot light-emitting structure. In addition, the first quantum dot light-emitting layer can be directly patterned through an exposure process, so that the quantum dot light-emitting structure has high precision and small size, and further has high resolution.

For example, as shown in fig. 5, the quantum dot light emitting structure 100 includes: a substrate base plate 150; a first quantum dot light emitting layer 112 on the substrate base plate 150; and a second quantum dot light emitting layer 122 on the substrate base plate 150, the ligand content of the first quantum dot light emitting layer 112 being less than 60% of the ligand content of the second quantum dot light emitting layer 122. For example, the ligand content of the first quantum dot light emitting layer 112 is 50% of the ligand content of the second quantum dot light emitting layer 122. In the process of forming the first quantum dot light-emitting layer, the light-induced ligand remover releases the ligand remover under the irradiation of light through an exposure process to remove the first ligand of the exposed part of the first quantum dot light-emitting material layer, so that the exposed part of the first quantum dot light-emitting material layer is insoluble in the first rinsing solvent, thereby retaining and forming the first quantum dot light-emitting layer on the substrate. Therefore, the ligand content in the finally formed first quantum dot light-emitting layer is smaller. The above ligand content is a percentage of the mass of the ligand to the mass of the entire quantum dot light-emitting layer.

In some examples, the first quantum dot light emitting layer includes a first quantum dot with a surface modified with a first ligand, a first quantum dot with a surface that is not modified with a ligand, and a photo-induced ligand removal agent. That is, the first quantum dots from which the first ligands are not removed by the ligand remover and the remaining photo-induced ligand remover are also present inside the first quantum dot light-emitting layer.

In some examples, the photoligand remover comprises a photoacid generator. The photoacid generator generates hydrogen ions after being irradiated with light, and the hydrogen ions are combined with the first ligands, thereby removing the first ligands from the exposed portions of the first quantum dot light-emitting material layer. On the other hand, the photoacid generator is used to remove the first ligand, so that the influence on the luminous efficiency of the first quantum dot can be avoided. Of course, the embodiments of the present disclosure include, but are not limited to, the photo-induced ligand removal agent may also be other materials that can remove the first ligand from the first quantum dot.

For example, the photoacid generator includes at least one of a triazine-based compound, an iodonium-based compound, a sulfonium-based compound, and a perfluorobutyl-based compound.

In some examples, the first quantum dot light emitting layer is configured to emit blue light and the second quantum dot light emitting layer is configured to emit red light (light in the wavelength range 622-770 nm) or green light (light in the wavelength range 492-577 nm).

In some examples, as shown in fig. 5, the quantum dot light emitting structure 100 further includes: a first electrode 181 and an electron transport layer 190 disposed on the substrate base plate 150 in this order. For example, the material of the first electrode may be a conductive metal oxide, such as Indium Tin Oxide (ITO). The material of the electron transport layer may be zinc oxide (ZnO).

For example, the zinc oxide thin film may be formed using a deposition process or a sputtering process.

In some examples, as shown in fig. 5, the quantum dot light emitting structure 100 further includes: a hole transport layer 195 located on a side of each of the quantum dot light emitting layers 112, 122, 132 away from the substrate base plate 150, a hole injection layer 197, and a second electrode 182 located on a side of the hole transport layer 195 away from the substrate base plate 150, the material of the second electrode may be a metal, such as silver.

At least one embodiment of the present disclosure also provides a display device. Fig. 6 is a schematic diagram of a display device according to an embodiment of the disclosure. As shown in fig. 6, the display device 300 includes the quantum dot light emitting structure 100 of any one of the above. Therefore, the display device also has higher luminous performance and higher resolution, and specific reference can be made to the related description of the quantum dot luminous structure, which is not repeated herein.

For example, the display device may be an electronic product having a display function, such as a television, an electronic picture frame, an electronic album, a computer, a notebook computer, a tablet computer, a navigator, a smart phone, and the like.

The following points need to be explained:

(1) in the drawings of the embodiments of the present disclosure, only the structures related to the embodiments of the present disclosure are referred to, and other structures may refer to general designs.

(2) Features of the same embodiment of the disclosure and of different embodiments may be combined with each other without conflict.

The above description is intended to be exemplary of the present disclosure, and not to limit the scope of the present disclosure, which is defined by the claims appended hereto.