Colorful miniature LED structure and preparation method thereof

Abstract

The invention provides a color micro LED structure and a preparation method thereof, and belongs to the technical field of micro display. In one specific implementation mode of the embodiment, the color miniature LED structure comprises a single-color miniature LED structure, a quantum dot composite layer and a transparent protective layer which are sequentially arranged from bottom to top; and the quantum dot composite layer is a film formed by uniformly dispersing quantum dot materials in photoresist in an oligomer form. Therefore, according to the embodiment of the invention, the solid content of the quantum dot material in the quantum dot composite layer per unit thickness is improved by regulating and controlling the aggregation degree of the quantum dot material in the quantum dot composite layer, so that the quantum dot composite layer has relatively high scattering intensity, and relatively high photoluminescence quantum yield is kept; therefore, the absorption efficiency and the color conversion efficiency of the quantum dot composite layer in the color micro LED structure on the light of the single-color micro LED structure are improved.

Description

Technical Field

[0001] The present invention belongs to the field of micro-display technology, and in particular relates to a color micro-LED structure and a preparation method thereof. Background Art

[0002] In the future, both augmented reality (AR) glasses and virtual reality (VR) glasses will require ultra-high resolution (≥3000ppi) display optical machines that must simultaneously meet requirements such as ultra-high resolution, low power consumption, highly collimated light emission, and small size.

[0003] Micro-LED technology is a technology that miniaturizes, matrices, and thins LED chips. However, when the pixel size of Micro-LED is reduced to less than 10um, the red / green luminous efficiency will drop sharply, resulting in poor display effects and increased power consumption.

[0004] Quantum dot material is a new type of luminescent material with the characteristics of high luminous efficiency, narrow peak width, low power consumption, high collimation luminescence, and small volume requirements. The inventors of this application found during the relevant technical research that by utilizing the characteristics of quantum dot materials absorbing blue light and emitting red / green light efficiently, the quantum layer formed by the quantum dot material can be patterned and combined with the blue light Micro-LED to achieve full-color display. However, to realize this solution, certain technical requirements are put forward for the quantum dot composite layer, for example: the size of the quantum dot composite layer must match the patterning of the Micro-LED; the quantum dot composite layer must meet the high blue light absorption rate, etc.

[0005] At present, common methods for patterning quantum dot composite layers include inkjet printing, nanoimprinting, photolithography, etc. However, nanoimprinting cannot produce thicker quantum dot composite layers, that is, the quantum dot composite layer cannot achieve a high blue light absorption rate within the thickness that can be achieved by nanoimprinting technology; and nanoimprinting is not conducive to large-scale production, so nanoimprinting is rarely used in Micro-LED quantum dot color conversion technology. The common quantum dot inks suitable for inkjet printing and quantum dot photoresists suitable for photolithography on the market currently have the problem of low blue light absorption efficiency per unit thickness, which limits the application of quantum dots in Micro-LED full-color display. Summary of the invention

[0006] In response to the above-mentioned problems existing in the prior art, an embodiment of the present invention provides a color micro-LED structure and a preparation method thereof, which can increase the solid content of the quantum dot material per unit thickness of the quantum dot composite layer, thereby improving the absorption efficiency of the quantum dot composite layer for Micro-LED light.

[0007] According to a first aspect of an embodiment of the present invention, a color micro-LED structure is provided, comprising: a monochrome micro-LED structure, a quantum dot composite layer, and a transparent protective layer arranged in sequence from bottom to top; the quantum dot composite layer is a thin film formed by quantum dot materials being uniformly dispersed in a photoresist in the form of oligomers.

[0008] Optionally, the particle size of the quantum dot material is 5nm-20nm; the thickness of the quantum dot composite layer is 1-5um.

[0009] Optionally, the monochrome micro LED structure is a blue micro LED structure; the transparent protective layer is a glass or resin film; and the quantum dot composite layer is formed by overlaying a red quantum dot composite film and a green quantum dot composite film.

[0010] Optionally, the photoresist is one or more of positive photoresist, negative photoresist, and reverse photoresist.

[0011] According to the second aspect of an embodiment of the present invention, a method for preparing a colored micro-LED structure is also provided, comprising: mixing a first quantum dot material and a second quantum dot material with a first solvent, respectively, to generate a corresponding first mixed liquid and a second mixed liquid; adding a second solvent to the first mixed liquid and the second mixed liquid, respectively, to obtain a corresponding first oligomer solution and a second oligomer solution; wherein the polarity of the second solvent is much greater than the polarity of the first solvent; mixing the first oligomer solution and the second oligomer solution with the photoresist, respectively, to obtain a corresponding first quantum dot photoresist and a second quantum dot photoresist; preparing a colored micro-LED structure based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro-LED structure.

[0012] Optionally, the first solvent is one or more of n-octane, toluene, cyclohexane, and carbon tetrachloride; and / or the second solvent is ethanol.

[0013] Optionally, the second solvent is 0.1% to 30% by weight of the first mixed solution or the second mixed solution; and the added amount of the photoresist is 0.1% to 70% by weight of the first oligomer solution or the second oligomer solution.

[0014] Optionally, the color micro LED structure is prepared based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure, including: sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on a transparent substrate to obtain a color conversion structure; and bonding the color conversion structure to the monochrome micro LED structure to obtain a color micro LED structure.

[0015] Optionally, a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist are sequentially arranged on a transparent substrate to obtain a color conversion structure; including: spin coating the first quantum dot photoresist on the transparent substrate to obtain a first spin-coated layer; using a photolithography machine to expose the first spin-coated layer, developing it with a developer, and then curing it to obtain a patterned first quantum dot pixel array; spin coating the second quantum dot photoresist in the gap between the first quantum dot pixel array and the space formed by the transparent substrate to obtain a second spin-coated layer; using a photolithography machine to expose the second spin-coated layer, developing it with a developer, and then curing it to obtain a patterned second quantum dot pixel array; based on the overlay structure between the first quantum dot pixel array and the second quantum dot pixel array, a color conversion structure is obtained.

[0016] Optionally, a colored micro-LED structure is prepared based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro-LED structure; comprising: sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on the monochrome micro-LED structure to obtain a color conversion structure; and covering the upper surface of the color conversion structure with the transparent protective layer to obtain a colored micro-LED structure.

[0017] The embodiment of the present invention provides a color micro LED structure and a preparation method thereof, wherein the color micro LED structure comprises: a monochromatic micro LED structure, a quantum dot composite layer, and a transparent protective layer arranged in sequence from bottom to top; the quantum dot composite layer is a thin film formed by the quantum dot material being uniformly dispersed in the photoresist in the form of oligomers. Therefore, the embodiment adjusts the aggregation degree of the quantum dot material in the quantum dot composite layer to increase the solid content of the quantum dot material in the unit thickness of the quantum dot composite layer, so that the quantum dot composite layer has a higher scattering intensity and maintains a higher photoluminescence quantum yield, thereby improving the absorption efficiency and color conversion efficiency of the quantum dot composite layer in the color micro LED structure for the light of the monochromatic micro LED structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0019] Figure 1 A schematic diagram of a process for preparing a color micro-LED structure provided by an embodiment of the present invention;

[0020] Figure 2A schematic structural diagram of a colored micro-LED structure provided in Example 1 of the present invention; wherein, 10, Micro-LED structure, 12, red quantum dot composite film, 11, green quantum dot composite film, 13, transparent glass, 14, barrier layer, 101, first electrode, 102, first filling layer, 103, current diffusion layer, 104, first semiconductor layer, 105, first reflective layer, 106, first light-emitting layer, 107, second semiconductor layer. DETAILED DESCRIPTION

[0021] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0022] A color micro LED structure comprises: a monochrome micro LED structure, a quantum dot composite layer, and a transparent protective layer arranged in sequence from bottom to top; the quantum dot composite layer is a thin film formed by quantum dot materials being uniformly dispersed in a photoresist in the form of oligomers.

[0023] Specifically, there is no limitation on the color of the quantum dot material. For example, the quantum dot material can be selected from red quantum dot material and / or green quantum dot material.

[0024] The monochromatic micro LED structure is a blue micro LED structure; the transparent protective layer is a glass or resin film; and the quantum dot composite layer is formed by overlaying a red quantum dot composite film and a green quantum dot composite film.

[0025] In the preferred implementation of this embodiment, there is no limitation on the composition of the photoresist, as long as the oligomers can be evenly dispersed in the photoresist. The photoresist is one or more of positive photoresist, negative photoresist, and reverse photoresist.

[0026] In a preferred implementation manner of this embodiment, the thickness of the nanocrystal composite film is 1-10um; in order to improve the light conversion efficiency of the quantum dot composite layer and reduce the light crosstalk and stray light formed by the light generated by Micro-LED passing through the quantum dot composite layer; in a further preferred implementation manner, the thickness of the quantum dot composite layer is 1-5um, and the particle size of the quantum dot material is 5nm-20nm.

[0027] It should be noted that this embodiment does not specifically limit the amount of quantum dot material in the oligomer, because the amount of quantum dot material in the oligomer is determined by the dosage of the second solvent added during the preparation process.

[0028] In the preferred implementation of this embodiment, there is no limitation on the method for preparing the color micro-LED structure.

[0029] like Figure 1 , which is a schematic flow chart of a method for preparing a color micro-LED structure provided by an embodiment of the present invention.

[0030] The method for preparing a color micro-LED structure comprises at least the following steps:

[0031] S101, mixing a first quantum dot material and a second quantum dot material with a first solvent respectively to generate a corresponding first mixed liquid and a second mixed liquid;

[0032] S102, adding a second solvent to the first mixed solution and the second mixed solution respectively to obtain a corresponding first oligomer solution and a second oligomer solution; wherein the polarity of the second solvent is much greater than the polarity of the first solvent;

[0033] S103, mixing the first oligomer solution and the second oligomer solution with photoresists respectively to obtain corresponding first quantum dot photoresists and second quantum dot photoresists;

[0034] S104, preparing a color micro LED structure based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure.

[0035] Specifically, the first solvent and the second solvent are both organic solvents; the first solvent is a solvent with a relatively low polarity; and the second solvent is a solvent with a relatively high polarity. Adding the second solvent to the first mixed solution can cause the first quantum dot material in the first mixed solution to aggregate on a small scale to form a first oligomer solution; adding the second solvent to the second mixed solution can cause the second quantum dot material in the second mixed solution to aggregate on a small scale to form a second oligomer solution.

[0036] In order to enable the quantum dot material to be effectively aggregated and uniformly dispersed in the organic solvent, in a preferred embodiment, the first solvent is one or more of n-octane, toluene, cyclohexane, and carbon tetrachloride; and / or the second solvent is ethanol.

[0037] In order to effectively adjust the size of the oligomers while avoiding agglomeration of a large amount of quantum dot materials, it is necessary to control the addition ratio of the second solvent in the first mixed liquid or the second mixed liquid. In a preferred implementation of this embodiment, the second solvent is 0.1% to 30% by weight of the first mixed liquid or the second mixed liquid; the addition amount of the photoresist is 0.1% to 70% by weight of the first oligomer solution or the second oligomer solution.

[0038] In a preferred implementation manner of this embodiment, the color micro LED structure is prepared based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure, including: sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on a transparent substrate to obtain a color conversion structure; and bonding the color conversion structure to the monochrome micro LED structure to obtain a color micro LED structure.

[0039] Specifically, there is no limitation on the arrangement of the first quantum dot pixel array and the second quantum dot pixel array on the transparent substrate. For example: the first quantum dot photoresist is spin-coated on the transparent substrate to obtain a first spin-coated layer; the first spin-coated layer is exposed to light by a photolithography machine, and then developed with a developer, and then cured to obtain a patterned first quantum dot pixel array; the second quantum dot photoresist is spin-coated in the gap between the first quantum dot pixel array and the space formed by the transparent substrate to obtain a second spin-coated layer; the second spin-coated layer is exposed to light by a photolithography machine, and then developed with a developer, and then cured to obtain a patterned second quantum dot pixel array; based on the overlay structure between the first quantum dot pixel array and the second quantum dot pixel array, a color conversion structure is obtained.

[0040] For example: the first quantum dot photoresist is spin-coated onto a glass substrate and desolvated to obtain a first spin-coated layer of a preset thickness; the first spin-coated layer is then exposed to light by a photolithography machine and developed with a developer to obtain a first developed coating; the first developed coating is baked and cured to obtain a patterned first quantum dot pixel array. The second quantum dot photoresist is spin-coated in the gap between the first quantum dot pixel array and the space formed by the glass substrate and desolvated to obtain a second spin-coated layer of a preset thickness; the second spin-coated layer is then exposed to light by a photolithography machine and developed with a developer to obtain a second developed coating; the second developed coating is baked and cured to obtain a patterned second quantum dot pixel array. Thus, a color conversion structure is obtained based on the overlay structure between the first quantum dot pixel array and the second quantum dot pixel array.

[0041] The color conversion structure is bonded to the monochrome micro-LED structure and then packaged to obtain a color micro-LED structure.

[0042] This embodiment is based on the scattering produced by the oligomers in the quantum dot composite layer, thereby increasing the optical path of the blue light in the quantum dot composite layer in the color Micro-LED structure, improving the absorption efficiency of the unit thickness of the quantum dot composite layer for the blue light in the Micro-LED, thereby reducing the optical crosstalk and stray light problems caused by the quantum dot composite layer to the blue light, improving the light conversion efficiency of the quantum dot composite layer, and realizing the full-color display of Micro-LED.

[0043] like Figure 2 , which is a schematic diagram of the structure of the color micro LED structure provided in Example 1 of the present invention.

[0044] Example 1

[0045] A color micro-LED structure comprises: a blue Micro-LED structure 10, a quantum dot composite layer, and a transparent glass 13 arranged in sequence from bottom to top; the quantum dot composite layer is formed by engraving a red quantum dot composite film 12 and a green quantum dot composite film 11. Four barrier layers 14 are arranged in sequence on the Micro-LED structure; the four barrier layers 14 are respectively: a first barrier layer, a second barrier layer, a third barrier layer, and a fourth barrier layer; the first barrier layer, the second barrier layer, and the upper surface of the Micro-LED structure enclose a first space; the second barrier layer, the third barrier layer, and the upper surface of the Micro-LED structure enclose a second space; the third barrier layer, the fourth barrier layer, and the upper surface of the Micro-LED structure enclose a third space; the red quantum dot composite film 12 is arranged in the first space, and the green quantum dot composite film 11 is arranged in the second space; the third space is not filled with any material; the transparent glass is attached to the upper end of the barrier layer, and the barrier layer can not only support the transparent glass, but also play a blocking role for the green quantum dot composite film 11 and the red quantum dot composite film 12. The particle size of the quantum dot material is 5nm-20nm; the thickness of the quantum dot composite layer is 1-5um. The blue Micro-LED structure 10 includes a first electrode 101, a first filling layer 102, a current diffusion layer 103, a first semiconductor layer 104, a first light reflecting layer 105, a first light emitting layer 106, and a second semiconductor layer 107 arranged in sequence from bottom to top.

[0046] The method for preparing the above-mentioned color micro-LED structure comprises at least the following steps:

[0047] S1, dissolving a red quantum dot material and a green quantum dot material in toluene respectively to obtain a first mixed solution and a second mixed solution;

[0048] S2, taking 1 mL of the first mixed solution and slowly adding 100 uL of ethanol thereto while stirring to obtain a first oligomer solution; taking 1 mL of the second mixed solution and slowly adding 100 uL of ethanol thereto while stirring to obtain a second oligomer solution;

[0049] S3, adding a negative photoresist to the first oligomer solution and stirring evenly to generate a first quantum dot photoresist; adding a negative photoresist to the second oligomer solution and stirring evenly to generate a second quantum dot photoresist;

[0050] S4, spin coating the first quantum dot photoresist onto the transparent glass substrate, with a spin coating thickness of about 2 um; and then baking at 80° C. for 30 min to remove the toluene and ethanol solvents in the first quantum dot photoresist, to obtain a 2 um first spin coating layer;

[0051] S5, exposing the first spin-coated layer by using a stepper photolithography machine and then developing it with a developer to obtain a first developed coating layer; baking the first developed coating layer at 140° C. for 30 minutes to completely solidify the first developed coating layer to obtain a patterned first quantum dot pixel array.

[0052] S6, spin-coating a second quantum dot photoresist with a thickness of about 2 μm in the space formed by the gap between the first quantum dot pixel array and the glass substrate, and then baking at 80° C. for 30 min to remove the toluene and ethanol solvents in the second quantum dot photoresist to obtain a second spin-coated layer with a thickness of 2 μm;

[0053] S7, exposing the second spin-coated layer by using a stepper photolithography machine and then developing it with a developer to obtain a second developed coating layer; baking the second developed coating layer at 140° C. for 30 minutes to completely cure the second developed coating layer to obtain a patterned second quantum dot pixel array.

[0054] S8, obtaining a color conversion structure based on the overlay structure between the patterned first quantum dot pixel array and the second quantum dot pixel array;

[0055] S9, after bonding the color conversion structure to the blue Micro-LED structure of the inverted vertical structure, a QDCC Micro-LED structure with full-color display of red, green and blue can be obtained.

[0056] This embodiment can increase the solid content of the quantum dot material in the quantum dot composite layer by aggregating the quantum dot material, thereby reducing the use of other scattering particles in the quantum dot composite layer and improving the absorption efficiency of the quantum dot composite layer for Micro-LED light, thereby solving the technical problem in the prior art of introducing other scattering particles in order to improve the absorption efficiency of the quantum dot material for Micro-LED light, thereby reducing the luminous efficiency of the quantum dot material.

[0057] Moreover, this embodiment can enable the color micro-LED structure to achieve a high blue light absorption rate when the thickness of the quantum dot composite layer is low; thereby, not only the optical crosstalk and light scattering of the blue light in the Micro-LED are reduced, but also the packaging difficulty of the optical components is reduced while achieving the full-color display effect of the color micro-LED structure, thereby improving the weather resistance of the optical components.

[0058] Comparative Example

[0059] An optical module includes: a blue Micro-LED, a conventional quantum dot composite layer, and transparent glass; wherein the conventional quantum dot composite layer is formed by overlapping a conventional red quantum dot composite film and a conventional green quantum dot composite film. Four barrier layers are arranged on the Micro-LED structure in sequence; the four barrier layers are: the first barrier layer, the second barrier layer, the third barrier layer and the fourth barrier layer; the first barrier layer, the second barrier layer, and the upper surface of the Micro-LED structure form a first space; the second barrier layer, the third barrier layer, and the upper surface of the Micro-LED structure form a second space; the third barrier layer, the fourth barrier layer, and the upper surface of the Micro-LED structure form a third space; a conventional red quantum dot composite film is arranged in the first space, and a conventional green quantum dot composite film is arranged in the second space; the third space is not filled with any material; the transparent glass is bonded to the upper end of the barrier layer and is arranged opposite to the Micro-LED, and the barrier layer can not only support the transparent glass, but also play a blocking role for the conventional red quantum dot composite film and the conventional green quantum dot composite film; a blue light filter layer is arranged on the conventional red quantum dot composite film and the conventional green quantum dot composite film. Among them, the blue Micro-LED includes a first electrode, a first filling layer, a current diffusion layer, a first semiconductor layer, a first reflective layer, a first light-emitting layer, and a second semiconductor layer arranged in sequence from bottom to top.

[0060] The method for preparing the optical module is similar to the method for preparing the color micro-LED structure of this embodiment, and will not be repeated here.

[0061] The comparative example needs to set a blue light filter layer to reduce the forward leakage of blue light. Compared with the comparative example, although the present embodiment does not set a blue light filter layer, the use of a quantum dot composite layer can reduce the optical crosstalk and light scattering of blue light in the Micro-LED; thereby improving the absorption efficiency of the quantum dot composite layer of the color micro LED structure to the Micro LED light.

[0062] In summary, the optical module prepared based on the conventional quantum dot composite layer has stray light, optical crosstalk, and blue light leakage; while the color micro-LED structure prepared in this embodiment has no optical crosstalk and the stray light is significantly reduced.

[0063] The quantum dot composite layer in the color micro-LED structure prepared in this embodiment has an absorption rate of 99% for blue light in the Micro-LED, and an absorbance of 2 at a wavelength of 460nm.

[0064] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0065] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0066] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0067] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0068] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

[0069] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0070] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0071] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A color micro LED structure, characterized in that: include: A monochrome micro LED structure, a quantum dot composite layer, and a transparent protective layer are arranged in sequence from bottom to top; the quantum dot composite layer is a thin film formed by quantum dot materials being uniformly dispersed in the photoresist in the form of oligomers.

2. The color micro-LED structure according to claim 1, characterized in that: The particle size of the quantum dot material is 5nm-20nm; the thickness of the quantum dot composite layer is 1-5um.

3. The color micro-LED structure according to claim 1, characterized in that: The monochromatic micro-LED structure is a blue micro-LED structure; The transparent protective layer is glass or resin film; The quantum dot composite layer is formed by overlaying a red quantum dot composite film and a green quantum dot composite film.

4. The color micro-LED structure according to claim 1, characterized in that: The photoresist is one or more of positive photoresist, negative photoresist and reverse photoresist.

5. A method for preparing a color micro-LED structure, characterized in that: include: Mixing the first quantum dot material and the second quantum dot material with the first solvent respectively to generate a corresponding first mixed liquid and a second mixed liquid; Adding a second solvent to the first mixed solution and the second mixed solution respectively to obtain a first oligomer solution and a second oligomer solution respectively; wherein the polarity of the second solvent is much greater than the polarity of the first solvent; The first oligomer solution and the second oligomer solution are mixed with the photoresist respectively to obtain a first quantum dot photoresist and a second quantum dot photoresist; A color micro LED structure is prepared based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure.

6. The method according to claim 5, characterized in that The first solvent is one or more of n-octane, toluene, cyclohexane, and carbon tetrachloride; and / or the second solvent is ethanol.

7. The method according to claim 5, characterized in that The second solvent is 0.1% to 30% by weight of the first mixed solution or the second mixed solution; The added amount of the photoresist is 0.1% to 70% of the weight of the first oligomer solution or the second oligomer solution.

8. The method according to claim 5, characterized in that The color micro LED structure is prepared based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure, including: sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on a transparent substrate to obtain a color conversion structure; The color conversion structure is laminated to a monochrome micro-LED structure to obtain a color micro-LED structure.

9. The method according to claim 8, characterized in that The method comprises sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on a transparent substrate to obtain a color conversion structure; comprising: Spin coating the first quantum dot photoresist on the transparent substrate to obtain a first spin coating layer; Exposing the first spin-coated layer by using a photolithography machine, developing it with a developer, and then curing it to obtain a patterned first quantum dot pixel array; Spin coating the second quantum dot photoresist in the space formed by the gaps of the first quantum dot pixel array and the transparent substrate to obtain a second spin coating layer; Exposing the second spin-coated layer by using a photolithography machine, developing it with a developer, and then curing it to obtain a patterned second quantum dot pixel array; Based on the overlay structure between the first quantum dot pixel array and the second quantum dot pixel array, a color conversion structure is obtained.

10. The method according to claim 5, characterized in that The method of preparing a color micro LED structure based on the first quantum dot photoresist, the second quantum dot photoresist, and the monochrome micro LED structure comprises: sequentially arranging a first quantum dot pixel array formed by the first quantum dot photoresist and a second quantum dot array formed by the second quantum dot photoresist on a monochrome micro LED structure to obtain a color conversion structure; The transparent protective layer is covered on the upper surface of the color conversion structure to obtain a color micro LED structure.

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