Micro LED device manufacturing method, micro LED device and display device

Abstract

The present disclosure provides a method for preparing a micro-LED device, a micro-LED device, and a display device. The method comprises: obtaining a micro-LED structure comprising a micro-LED unit array; disposing an array of spacer structures on a light-emitting side surface of the micro-LED structure, each spacer structure comprising a reflective material layer and a first protective layer disposed on its sidewall; disposing a refractive material layer on the top surface of the spacer structure, such that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, each spacer structure and the corresponding refractive material layer forming an isolation structure, and forming a receiving space between two adjacent spacer structures, all of the receiving spaces forming an array of receiving spaces corresponding to the micro-LED unit array, the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer being greater than a preset value; and filling the array of receiving spaces with quantum dots to form a quantum dot array, thereby obtaining a micro-LED device.

Description

Technical Field

[0001] The present disclosure relates to the technical field of semiconductor Micro LEDs, and more particularly to a method for preparing a Micro LED device, a Micro LED device, and a display device. Background Art

[0002] With the continuous pursuit of display technology, it is gradually developing towards smaller sizes and higher resolutions. Micro LED is a representative example of miniaturized display technology. Micro LED technology involves miniaturizing, matrixing, and thin-filming LED chips, with pixel sizes less than 50μm. Currently, full-color Micro LED displays can be achieved using color conversion structures, which utilize quantum dot (QD) materials for color conversion. However, the preparation and structure of color conversion structures still present some challenges, making it difficult to meet the increasingly stringent requirements for light output efficiency brought about by pixel miniaturization. Summary of the Invention

[0003] The solution disclosed herein provides a method for preparing a micro LED device, a micro LED device, and a display device.

[0004] According to one aspect of an embodiment of the present disclosure, a method for preparing a micro-LED device is provided, wherein the method includes: obtaining a micro-LED structure, wherein the micro-LED structure includes a micro-LED chip, wherein the micro-LED chip includes a micro-LED unit array; providing an array of spacer structures on a light-emitting side surface of the micro-LED structure, wherein each spacer structure in the array of spacer structures includes a reflective material layer and a first protective layer provided on a sidewall of the reflective material layer, and a top surface of the spacer structure includes a top surface of the reflective material layer and a top surface of the first protective layer; providing a refractive material layer on the top surface of each spacer structure, such that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, wherein each spacer structure and the corresponding refractive material layer form an isolation structure, all of the isolation structures constitute an isolation structure array, and accommodation spaces are formed between two adjacent isolation structures, all of the accommodation spaces constitute an accommodation space array, the accommodation space array corresponding to the micro-LED unit array, wherein the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer is greater than a preset value; and filling the array of accommodation spaces with quantum dots to form a quantum dot array, thereby obtaining the micro-LED device.

[0005] Furthermore, each isolation substructure in the isolation substructure array also includes an isolation column, and the top surface of the isolation substructure also includes the top surface of the isolation column. The isolation substructure array is arranged on the surface of the light-emitting side of the micro-LED structure, including: arranging a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure, so that each through hole in the through hole array exposes a preset exposed portion of the surface of the light-emitting side of the micro-LED structure and corresponds to the micro-LED unit in the micro-LED unit array, and the isolation column is formed between two adjacent through holes; arranging a reflective material layer on the surface of the isolation column; arranging a first protective layer on the reflective material layer; removing the reflective material layer and the first protective layer above the top of the isolation column to expose the top surface of the isolation column, the top surface of the reflective material layer and the top surface of the first protective layer.

[0006] Further, a refractive material layer is arranged on the top surface of each of the isolation substructures so that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, including: a refractive material layer is arranged on the top surface of each of the isolation substructures so that the refractive material layer covers the top surface of the isolation column, the top surface of the reflective material layer and the top surface of the first protective layer.

[0007] Furthermore, before providing a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure, the method further includes: providing an insulating layer on the surface of the light-emitting side of the micro-LED structure, providing a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure, so that each through hole in the through hole array exposes a preset exposed portion of the surface of the light-emitting side of the micro-LED structure and corresponds to a micro-LED unit in the micro-LED unit array, and an isolation column is formed between two adjacent through holes, including: providing a first passivation layer on the insulating layer, and opening a through hole array on the first passivation layer, so that each through hole in the through hole array exposes a preset exposed portion of the insulating layer and corresponds to a micro-LED unit in the micro-LED unit array, and an isolation column is formed between two adjacent through holes.

[0008] Furthermore, each micro LED unit in the micro LED unit array includes a first semiconductor layer on the light-emitting side. Before setting the insulating layer on the surface of the light-emitting side of the micro LED structure, the method also includes: roughening the surface of the first semiconductor layer to obtain a first roughened surface. Setting the insulating layer on the surface of the light-emitting side of the micro LED structure includes: setting the insulating layer on the first roughened surface.

[0009] Furthermore, the isolation layer includes a plurality of sub-isolation layers, and arranging the isolation layer on the surface of the light-emitting side of the micro-LED structure includes: arranging the plurality of sub-isolation layers in sequence from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein each of the plurality of sub-isolation layers has a preset thickness and a preset refractive index, the total thickness of the plurality of sub-isolation layers is equal to half the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-isolation layers decreases in the order from bottom to top of the plurality of sub-isolation layers.

[0010] Furthermore, providing a reflective material layer on the surface of the isolation column includes: providing a reflective material layer on the top and sidewall of the isolation column and performing surface roughening treatment on the reflective material layer on the sidewall of the isolation column to obtain a second roughened surface.

[0011] Furthermore, the reflective material layer includes a metal layer, and arranging the reflective material layer on the top and side walls of the isolation column and performing surface roughening treatment on the reflective material layer on the side walls of the isolation column include: depositing a metal layer of a preset thickness on the top and side walls of the isolation column so that the grains of the metal layer on the side walls of the isolation column have a tendency to grow laterally; and annealing the metal layer so that a plurality of protrusions are formed on the surface of the metal layer on the side walls of the isolation column.

[0012] Furthermore, when providing a first protective layer on the reflective material layer, the method further includes: providing the first protective layer on the exposed insulating layer. The insulating layer includes a plurality of sub-insulating layers, and the plurality of sub-insulating layers are sequentially provided from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers each have a preset thickness and a preset refractive index, the total thickness of the plurality of sub-insulating layers is equal to one-quarter of the wavelength of light emitted by the micro-LED unit, the preset thickness of the first protective layer on the plurality of sub-insulating layers is equal to one-quarter of the wavelength of light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers decreases in the order of the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers from bottom to top.

[0013] Furthermore, the preset value is greater than or equal to 1.

[0014] Furthermore, the accommodating space array includes multiple groups of accommodating spaces, each group of accommodating spaces includes a first subspace, a second subspace and a third subspace, and filling quantum dots in the accommodating space array includes at least one of the following: filling green quantum dots in each first subspace; filling red quantum dots in each second subspace.

[0015] Furthermore, after filling quantum dots in the accommodating space array to form a quantum dot array, the method further comprises: providing an encapsulation layer on the quantum dot array and the isolation structure.

[0016] Furthermore, the encapsulation layer includes a first sub-encapsulation layer, and setting the encapsulation layer on the quantum dot array and the isolation structure includes: setting the first sub-encapsulation layer on the quantum dot array and the isolation structure; the first sub-encapsulation layer includes a second passivation layer and a filter film, and setting the first sub-encapsulation layer on the quantum dot array and the isolation structure includes: setting the second passivation layer on the quantum dot array and the isolation structure; and setting the filter film on the second passivation layer.

[0017] Furthermore, the encapsulation layer also includes a second sub-encapsulation layer, and setting the encapsulation layer on the quantum dot array and the isolation structure also includes: setting the second sub-encapsulation layer on the first sub-encapsulation layer; the second sub-encapsulation layer includes a microlens array, a sealant and a second protective layer, and setting the second sub-encapsulation layer on the first sub-encapsulation layer includes: setting a microlens array corresponding to the quantum dot array on the filter film; setting a sealant in the gaps of the microlens array; and setting a second protective layer on the microlens array and the sealant.

[0018] Furthermore, the micro LED structure also includes a driving substrate, and the driving substrate is bonded to the micro LED chip, or the driving substrate is not bonded to the micro LED chip. When the driving substrate is not bonded to the micro LED chip, after quantum dots are filled in the accommodating space array to form a quantum dot array, the method also includes: bonding the driving substrate to the micro LED chip.

[0019] Furthermore, the material of the isolation column includes silicon dioxide, the material of the metal layer includes aluminum, the material of the first protective layer includes magnesium fluoride, the material of the refractive material layer includes silicon nitride, and the first semiconductor layer includes an N-GaN layer.

[0020] According to another aspect of the present disclosure, a micro-LED device is also provided. The micro-LED device includes: a micro-LED structure including a micro-LED chip, wherein the micro-LED chip includes a micro-LED unit array; an isolation structure array, wherein a receiving space is formed between two adjacent isolation structures in the isolation structure array, and all of the receiving spaces constitute an receiving space array, wherein the receiving space array corresponds to the micro-LED unit array, and each isolation structure in the isolation structure array includes: an isolation substructure, which is arranged on the surface of the light-emitting side of the micro-LED structure and includes a reflective material layer and a first sub-protective layer arranged on the sidewall of the reflective material layer, wherein the top surface of the isolation substructure includes the top surface of the reflective material layer and the top surface of the first sub-protective layer; a refractive material layer, which is arranged on the top surface of the isolation substructure and covers the top surface of the reflective material layer and the top surface of the first sub-protective layer, wherein the difference between the refractive index of the refractive material layer and the refractive index of the first sub-protective layer is greater than a preset value; and a quantum dot array, wherein the quantum dots in the quantum dot array are filled in the receiving spaces in the receiving space array.

[0021] Furthermore, the isolation substructure also includes an isolation column, the top surface of the isolation substructure also includes the top surface of the isolation column, the isolation column is arranged on the surface of the light-emitting side of the micro-LED structure, the reflective material layer is arranged on the side wall of the isolation column, and the first sub-protective layer is arranged on the side wall of the reflective material layer.

[0022] Further, the refractive material layer is arranged on the top surface of the isolation column, the top surface of the reflective material layer and the top surface of the first sub-protective layer and covers the top surface of the isolation column, the top surface of the reflective material layer and the top surface of the first sub-protective layer.

[0023] Furthermore, the micro LED device further includes an insulating layer, which is arranged on the surface of the light-emitting side of the micro LED structure, and the isolation column is arranged on the insulating layer.

[0024] Furthermore, each micro LED unit in the micro LED unit array includes a first semiconductor layer on the light-emitting side, the first semiconductor layer includes a first roughened surface, and the isolation layer is provided on the first roughened surface.

[0025] Furthermore, the isolation layer includes a plurality of sub-isolation layers, which are arranged in sequence from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein each of the plurality of sub-isolation layers has a preset thickness and a preset refractive index, the total thickness of the plurality of sub-isolation layers is equal to half the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-isolation layers decreases in the order from bottom to top of the plurality of sub-isolation layers.

[0026] Furthermore, the reflective material layer includes a metal layer, the metal layer includes a second roughened surface, and the second roughened surface includes a plurality of protrusions.

[0027] Furthermore, the micro LED device also includes a second sub-protective layer, which is arranged on the insulating layer in each accommodating space, and the second sub-protective layer and the first sub-protective layer are of the same material and integrally constitute the first protective layer. The insulating layer includes multiple sub-isolation layers, and the multiple sub-isolation layers are arranged in sequence from bottom to top on the surface of the light-emitting side of the micro LED structure, wherein the multiple sub-isolation layers and the second sub-protective layer on the multiple sub-isolation layers each have a preset thickness and a preset refractive index, the total thickness of the multiple sub-isolation layers is equal to one-quarter of the wavelength of the light emitted by the micro LED unit, the preset thickness of the second sub-protective layer on the multiple sub-isolation layers is equal to one-quarter of the wavelength of the light emitted by the micro LED unit, and the preset refractive index of the multiple sub-isolation layers and the second sub-protective layer on the multiple sub-isolation layers decreases in the bottom-up order of the multiple sub-isolation layers and the second sub-protective layer on the multiple sub-isolation layers.

[0028] Furthermore, the preset value is greater than or equal to 1.

[0029] Furthermore, the accommodating space array includes multiple groups of accommodating spaces, each group of accommodating spaces includes a first subspace, a second subspace and a third subspace, each first subspace is filled with green quantum dots, and each second subspace is filled with red quantum dots.

[0030] Furthermore, the micro LED device further includes an encapsulation layer, which is disposed on the quantum dot array and the isolation structure.

[0031] Furthermore, the encapsulation layer includes a first sub-encapsulation layer, which is arranged on the quantum dot array and the isolation structure. The first sub-encapsulation layer includes a second passivation layer and a filter film, and the second passivation layer is arranged on the quantum dot array and the isolation structure; the filter film is arranged on the second passivation layer.

[0032] Furthermore, the encapsulation layer also includes a second sub-encapsulation layer, which is arranged on the first sub-encapsulation layer. The second sub-encapsulation layer includes a microlens array, a sealant, and a second protective layer. The microlens array is arranged on the filter film and corresponds to the quantum dot array. The sealant is arranged in the gaps of the microlens array; the second protective layer is arranged on the microlens array and the sealant.

[0033] According to another aspect of the embodiments of the present disclosure, a display device is provided, comprising the aforementioned micro LED device.

[0034] By applying the technical solution disclosed herein, a color conversion structure is directly fabricated on a micro-LED structure by providing an isolation structure array on the micro-LED structure and providing quantum dots in the accommodation space between each two adjacent isolation structures. The isolation structure includes an isolation substructure and a refractive material layer. The isolation substructure includes a reflective material layer and a first protective layer provided on the sidewalls of the reflective material layer. The refractive material layer is provided on the top surface of the isolation substructure and contacts the top surface of the reflective material layer and the top surface of the first protective layer. Because the difference between the refractive index of the refractive material layer in the isolation structure and the refractive index of the first protective layer is greater than a preset value, the refractive material layer can disrupt the waveguide propagation of light in the first protective layer and along the sidewalls of the reflective material layer, reflecting the light into the quantum dots, thereby increasing the light involved in exciting the quantum dots and thereby improving the light utilization rate, thereby increasing the light output of the micro-LED device ultimately formed.

[0035] Furthermore, the reflective material layer can enhance the reflection of light emitted toward the isolation structure, causing the light to be reflected into the quantum dots, thereby increasing the light involved in exciting the quantum dots, thereby improving the utilization of light and reducing the crosstalk of light through the isolation structure to adjacent quantum dots. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an illustrative and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0037] Figure 1 is a flow chart illustrating a method for preparing a micro LED device according to one embodiment of the present disclosure;

[0038] Figures 2 to 13 1 is a schematic diagram illustrating a process flow of a method for preparing a micro LED device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0039] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0040] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0041] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways, rotated 90 degrees or in other orientations, and the spatially relative descriptions used herein are interpreted accordingly.

[0042] Now, exemplary embodiments according to the present disclosure will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be construed as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of this application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for clarity, the thickness of layers and regions is exaggerated, and the same reference numerals are used to represent the same devices, and thus their descriptions will be omitted.

[0043] The present disclosure provides a method for preparing a micro LED device. Figures 1 to 13 , Figure 1 is a flow chart illustrating a method for preparing a micro LED device according to one embodiment of the present disclosure; Figures 2 to 13 1 is a schematic diagram illustrating a process flow of a method for preparing a micro LED device according to an embodiment of the present disclosure.

[0044] According to embodiments of the present disclosure, the pixel size in the micro LED device is typically less than 50 microns.

[0045] like Figure 1 As shown, the method for preparing a micro LED device includes the following steps S101-S104.

[0046] Step S101: Acquire a micro LED structure, where the micro LED structure includes a micro LED chip, and the micro LED chip includes a micro LED unit array.

[0047] Step S102: An isolation substructure array is provided on the surface of the light-emitting side of the micro-LED structure, wherein each isolation substructure in the isolation substructure array includes a reflective material layer and a first protective layer provided on the sidewall of the reflective material layer, and the top surface of the isolation substructure includes the top surface of the reflective material layer and the top surface of the first protective layer.

[0048] Step S103: a refractive material layer is provided on the top surface of each of the isolation substructures, so that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, wherein each of the isolation substructures and the corresponding refractive material layer form an isolation structure, all of the isolation structures constitute an isolation structure array, and an accommodation space is formed between two adjacent isolation structures, all of the accommodation spaces constitute an accommodation space array, and the accommodation space array corresponds to the micro LED unit array, wherein the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer is greater than a preset value.

[0049] Step S104: filling quantum dots in the accommodating space array to form a quantum dot array to obtain the micro LED device.

[0050] According to this technical solution, a color conversion structure is fabricated directly on a micro-LED structure by providing an array of isolation structures on the micro-LED structure and disposing quantum dots in the spaces between each pair of adjacent isolation structures. The isolation structure comprises an isolation substructure and a refractive material layer. The isolation substructure comprises a reflective material layer and a first protective layer disposed on the sidewalls of the reflective material layer. The refractive material layer is disposed on the top surface of the isolation substructure and contacts the top surfaces of both the reflective material layer and the first protective layer. Because the difference in refractive index between the refractive material layer in the isolation structure and the first protective layer is greater than a predetermined value, the refractive material layer disrupts the waveguide propagation of light in the first protective layer and along the sidewalls of the reflective material layer, reflecting light into the quantum dots. This increases the amount of light involved in exciting the quantum dots, thereby improving light utilization and increasing the light output of the resulting micro-LED device. Furthermore, the reflective material layer enhances the reflection of light emitted toward the isolation structure, causing it to reflect into the quantum dots, thereby increasing the amount of light involved in exciting the quantum dots. This improves light utilization and reduces crosstalk between the isolation structure and adjacent quantum dots.

[0051] In step S101 , a micro LED structure may be obtained, where the micro LED structure includes a micro LED chip, and the micro LED chip includes a micro LED unit array.

[0052] According to the embodiments of the present disclosure, a micro-LED structure for emitting light can be first obtained. The micro-LED structure can include a micro-LED chip, which can include a micro-LED unit array. The micro-LED unit array can be any micro-LED unit array suitable for preparing a micro-LED device. For example, the structure of the micro-LED unit array can include a face-up structure, a flip-chip structure, or a vertical structure, etc., without limitation. The micro-LED structure can also include a driver substrate, which can be bonded to the micro-LED chip or unbonded to the micro-LED chip. When the driver substrate and the micro-LED chip are bonded together, a color conversion structure can be prepared on the micro-LED structure including the bonded driver substrate and micro-LED chip. When the driver substrate and the micro-LED chip are unbonded, after filling the receiving space array with quantum dots to form the quantum dot array, the method can further include: bonding the driver substrate to the micro-LED chip.

[0053] Reference Figure 2-13 ,in Figure 2 FIG. 1 shows a side view of a micro LED structure 10 according to one embodiment of the present disclosure. Figure 2 As shown, the micro LED structure 10 includes a driving substrate 102 and a micro LED chip 101 bonded to the driving substrate 102. The micro LED chip 101 includes a micro LED unit array composed of micro LED units 1011. It is worth noting that for the sake of simplicity and clarity, Figure 2 Only three micro LED units 1011 are schematically shown. The number of micro LED units can be determined according to actual needs and is not limited here.

[0054] In step S102, an isolation substructure array can be set on the surface of the light-emitting side of the micro-LED structure, wherein each isolation substructure in the isolation substructure array includes a reflective material layer and a first protective layer arranged on the side wall of the reflective material layer, and the top surface of the isolation substructure includes the top surface of the reflective material layer and the top surface of the first protective layer.

[0055] According to an embodiment of the present disclosure, each isolation substructure in the isolation substructure array further includes an isolation column, and the top surface of the isolation substructure further includes the top surface of the isolation column. Arranging the isolation substructure array on the surface of the light-emitting side of the micro-LED structure includes: arranging a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure, so that each through hole in the through hole array exposes a preset exposed portion of the surface of the light-emitting side of the micro-LED structure and corresponds to a micro-LED unit in the micro-LED unit array, and the isolation column is formed between two adjacent through holes; arranging a reflective material layer on the surface of the isolation column; arranging a first protective layer on the reflective material layer; removing the reflective material layer and the first protective layer above the top of the isolation column to expose the top surface of the isolation column, the top surface of the reflective material layer, and the top surface of the first protective layer. Wherein, the material of the first passivation layer may include silicon dioxide, and therefore the material of the isolation column includes silicon dioxide. Of course, the material of the first passivation layer may also include any other applicable material.

[0056] According to an embodiment of the present disclosure, before providing a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure, the method may further include: providing an insulating layer on the surface of the light-emitting side of the micro-LED structure so as to protect the micro-LED structure when other layers or structures are provided on the micro-LED structure. Furthermore, providing a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro-LED structure such that each through hole in the array of through holes exposes a predetermined exposed portion of the surface of the light-emitting side of the micro-LED structure and corresponds to a micro-LED unit in the micro-LED unit array, and forming an isolation column between two adjacent through holes may include: providing a first passivation layer on the isolation layer, and providing an array of through holes on the first passivation layer such that each through hole in the array of through holes exposes a predetermined exposed portion of the isolation layer and corresponds to a micro-LED unit in the micro-LED unit array, and forming an isolation column between two adjacent through holes.

[0057] Furthermore, each micro LED unit in the micro LED unit array includes a first semiconductor layer on the light emitting side. Before providing an insulating layer on the surface of the light emitting side of the micro LED structure, the method may further include: roughening the surface of the first semiconductor layer to obtain a first roughened surface. And providing an insulating layer on the surface of the light emitting side of the micro LED structure may include: providing an insulating layer on the first roughened surface. The first semiconductor layer may be, for example, an N-GaN layer, or of course a P-GaN layer. Since the first roughened surface of the first semiconductor layer of the micro LED unit is the light emitting surface of the micro LED unit, the roughening of the light emitting surface can destroy the total reflection condition of light on the surface, thereby reducing the reflection of light toward the inside of the micro LED chip, and further increasing the emission of light.

[0058] According to an embodiment of the present disclosure, the insulation layer may include multiple sub-insulation layers. Disposing the insulation layer on the light-emitting surface of the micro-LED structure may include: sequentially disposing the multiple sub-insulation layers from bottom to top on the light-emitting surface of the micro-LED structure, wherein each of the multiple sub-insulation layers has a preset thickness and a preset refractive index, the total thickness of the multiple sub-insulation layers being equal to half the wavelength of light emitted by the micro-LED unit, and the preset refractive index of each of the multiple sub-insulation layers decreasing in order from bottom to top. The multiple sub-insulation layers are arranged in this manner such that the refractive index of each insulation layer decreases from bottom to top, thereby reducing Fresnel loss of light and allowing more light to pass through the insulation layer. Furthermore, since the total thickness of the multiple sub-insulation layers is equal to half the wavelength of light emitted by the micro-LED unit, the total thickness satisfies the optically enhanced transmittance thickness, thereby further increasing the amount of light passing through the insulation layer. Regarding the preset thickness and refractive index of each of the multiple sub-insulation layers, the corresponding material can be selected based on the preset refractive index of each sub-insulation layer, and the thickness of each sub-insulation layer can be pre-set based on the actual required total insulation layer thickness.

[0059] Reference Figure 2-13 ,in Figure 3 FIG. 2 shows a side view of an insulating layer 201 disposed on a micro LED structure 10 according to an embodiment of the present disclosure. Figure 3As shown, each micro LED unit 1011 in the micro LED unit array may include a first semiconductor layer, such as an N-GaN layer, on the light-emitting side, and the surface of the first semiconductor layer is the light-emitting surface. The surface of the first semiconductor layer may be roughened by dry etching or wet etching to obtain a first roughened surface 10111, and then an isolation layer 201 may be deposited on the first roughened surface 10111 by chemical vapor deposition (CVD). Specifically, the isolation layer 201 may include a plurality of sub-isolation layers. For example, a tantalum pentoxide (Ta2O5) layer, a yttrium trioxide (Y2O3) layer, and a silicon dioxide layer may be sequentially deposited from bottom to top on the first roughened surface 10111 as three sub-isolation layers. The sum of the thicknesses of the three sub-isolation layers is equal to half the wavelength of the light emitted by the micro LED unit 1011, and the refractive indices of the three sub-isolation layers decrease in order from bottom to top.

[0060] Reference Figure 2-13 ,in Figure 4 FIG. 2 shows a side view of an isolation column 202 provided on an isolation layer 201 according to an embodiment of the present disclosure. Figure 4 As shown, a silicon dioxide layer, for example, can be deposited on the isolation layer 201 by chemical vapor deposition (CVD) as a first passivation layer. Then, for example, a through-hole array consisting of through-holes 2021 can be opened on the first passivation layer by photolithography and etching techniques, so that each through-hole 2021 in the through-hole array exposes a preset exposed portion of the isolation layer 201 and corresponds to the micro LED unit 1011 in the micro LED unit array, and an isolation column 202 is formed between two adjacent through-holes 2021, that is, the portion remaining after photolithography and etching of the first passivation layer is the isolation column 202.

[0061] According to an embodiment of the present disclosure, after forming the isolation column, a reflective material layer may be provided on the surface of the isolation column. Compared with the material of the passivation layer, the reflective material layer is more likely to reflect light toward the reflective material layer.

[0062] Furthermore, providing a reflective material layer on the surface of the isolation pillar may include providing a reflective material layer on the top and sidewalls of the isolation pillar and performing a surface roughening treatment on the reflective material layer on the sidewalls of the isolation pillar to obtain a second roughened surface. The second roughened surface can disrupt the propagation of light along the reflective material layer, thereby causing more light to be reflected.

[0063] Specifically, the reflective material layer may include any suitable material layer, such as a metal layer. Providing the reflective material layer on the top and sidewalls of the isolation pillar and performing a surface roughening treatment on the reflective material layer on the sidewalls of the isolation pillar may include: depositing a metal layer of a predetermined thickness on the top and sidewalls of the isolation pillar such that the grains of the metal layer on the sidewalls of the isolation pillar have a tendency to grow laterally; and annealing the metal layer such that a plurality of protrusions are formed on the surface of the metal layer on the sidewalls of the isolation pillar. The metal layer may be made of any suitable metal, such as aluminum.

[0064] Reference Figure 2-13 ,in Figure 5 FIG. 2 shows a side view of a reflective material layer 203 disposed on an isolation column 202 according to an embodiment of the present disclosure. Figure 5 As shown, the pattern of the reflective material layer 203 can be formed by photolithography using a photoresist, and then the reflective material layer 203, such as an aluminum layer, is deposited on the isolation column 202, such as a silicon dioxide material, using a physical vapor deposition (PVD) method and the reflective material layer 203 is annealed to obtain the following: Figure 5 The structure shown in FIG. When depositing a reflective material layer 203, such as an aluminum layer, the reflective material layer 203 has a predetermined thickness. That is, the reflective material layer 203 can be a thin layer on the isolation pillar 202, such as a silicon dioxide layer, according to process requirements. This causes the lattice direction of the reflective material layer 203, such as an aluminum layer, on the sidewall of the isolation pillar 202, such as a silicon dioxide layer, to change from the traditional vertical direction to the horizontal direction. As a result, the grains of the reflective material layer 203, such as an aluminum layer, on the sidewall of the isolation pillar 202, such as a silicon dioxide layer, have a lateral growth tendency. The reflective material layer 203 is then annealed to release the grain stress of the reflective material layer 203, such as the aluminum layer, along the lattice direction, thereby forming a plurality of protrusions on the surface of the reflective material layer 203 on the sidewall of the isolation pillar 202, thereby forming a second roughened surface 2031 of the reflective material layer 203.

[0065] According to an embodiment of the present disclosure, after providing a reflective material layer, a first protective layer may be provided on the reflective material layer. The material of the first protective layer may include magnesium fluoride. The first protective layer provided on the reflective material layer may protect the reflective material layer from damage during subsequent processes.

[0066] According to an embodiment of the present disclosure, when a first protective layer is provided on the reflective material layer, the method further includes: providing the first protective layer on the exposed insulating layer. The insulating layer may include a plurality of sub-insulating layers, and the plurality of sub-insulating layers are sequentially provided from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers each have a preset thickness and a preset refractive index, the total thickness of the plurality of sub-insulating layers is equal to one-quarter of the wavelength of light emitted by the micro-LED unit, the preset thickness of the first protective layer on the plurality of sub-insulating layers is equal to one-quarter of the wavelength of light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers decreases in the order of the plurality of sub-insulating layers and the first protective layer on the plurality of sub-insulating layers from bottom to top. The multiple sub-isolating layers and the first protective layer above the multiple sub-isolating layers are arranged in this manner, so that the refractive index of each isolation layer and the first protective layer above the isolation layer gradually decreases from bottom to top, thereby reducing Fresnel loss of light, allowing more light to pass through the isolation layer and the first protective layer. At the same time, because the total thickness of the multiple sub-isolating layers and the first protective layer above the multiple sub-isolating layers is equal to half the wavelength of light emitted by the micro-LED unit, this total thickness meets the optical anti-reflection thickness requirement, thereby further increasing the light passing through the isolation layer. Regarding the preset thickness and preset refractive index of each of the multiple sub-isolating layers, the corresponding material can be selected based on the preset refractive index of each sub-isolating layer, and the thickness of each sub-isolating layer can be pre-set based on the actual required total isolation layer thickness.

[0067] Reference Figure 2-13 ,in Figure 6 FIG. 2 shows a side view of a first protective layer 204 disposed on a reflective material layer 203 according to an embodiment of the present disclosure. Figure 6 As shown, a first protective layer 204, such as magnesium fluoride, can be deposited on the reflective material layer 203 and the exposed insulating layer 201 by chemical vapor deposition (CVD). Specifically, the insulating layer 201 can include multiple sub-insulating layers. For example, a tantalum pentoxide (Ta2O5) layer, a yttrium trioxide (Y2O3) layer, and a silicon dioxide layer can be deposited sequentially from bottom to top on the surface of the light-emitting side of the micro-LED structure 10. The sum of the thicknesses of the three sub-insulating layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit 1011. The thickness of the first protective layer, such as magnesium fluoride, on the three sub-insulating layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit 1011. In addition, the refractive indices of the three sub-insulating layers and the first protective layer on the three sub-insulating layers decrease in order from bottom to top.

[0068] According to an embodiment of the present disclosure, after providing the first protective layer, the reflective material layer and the first protective layer above the top of the isolation column can be removed to expose the top surface of the isolation column, the top surface of the reflective material layer and the top surface of the first protective layer.

[0069] Reference Figure 2-13 ,in Figure 7 FIG. 2 shows a side view of the exposed top surface 2024 of the isolation pillar, the top surface 2034 of the reflective material layer, and the top surface 2044 of the first protective layer according to an embodiment of the present disclosure. Figure 7 As shown, the reflective material layer such as aluminum and the first protective layer above the top of the isolation column 202 are removed by photolithography and lift-off processes until the top surface 2024 of the isolation column is exposed. At this time, the reflective material layer such as aluminum 203 has an exposed top surface 2034, and the first protective layer 204 has an exposed top surface 2044.

[0070] In step S103, a refractive material layer can be provided on the top surface of each of the isolation substructures, so that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, wherein each of the isolation substructures and the corresponding refractive material layer form an isolation structure, all of the isolation structures constitute an isolation structure array, and an accommodation space is formed between two adjacent isolation structures, all of the accommodation spaces constitute an accommodation space array, and the accommodation space array corresponds to the micro LED unit array, wherein the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer is greater than a preset value.

[0071] According to an embodiment of the present disclosure, as described in step S102, each of the isolating substructures in the isolating substructure array further includes an isolating column, and the top surface of the isolating substructure further includes the top surface of the isolating column. Therefore, disposing a refractive material layer on the top surface of each of the isolating substructures such that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer may include: disposing a refractive material layer on the top surface of each of the isolating substructures such that the refractive material layer covers the top surface of the isolating column, the top surface of the reflective material layer, and the top surface of the first protective layer.

[0072] In this embodiment, the refractive material layer covers and contacts the top surface of the isolation column, the top surface of the reflective material layer, and the top surface of the first protective layer. The isolation column, the reflective material layer on the isolation column, the first protective layer on the isolation column, and the refractive material layer constitute an isolation structure, and a holding space is formed between every two adjacent isolation structures, thereby obtaining an array of holding spaces. It is worth noting that the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer is greater than a preset value, which can be determined according to actual applications. Preferably, the preset value is greater than or equal to 1. The difference between the refractive index of the refractive material layer and the refractive index of the first protective layer can destroy the waveguide propagation of light along the sidewall of the reflective material layer in the first protective layer, and enhance the reflection of light into the quantum point. The greater the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer, the more obvious the effect. Therefore, the material of the refractive material layer may include silicon nitride, and of course, any other suitable material.

[0073] Reference Figure 2-13 ,in Figure 8 FIG. 2 shows a side view of a refractive material layer 205 disposed on the exposed top surface 2024 of the isolation pillar, the top surface 2034 of the reflective material layer, and the top surface 2044 of the first protective layer according to an embodiment of the present disclosure. Figure 8 As shown, a refractive material layer 205, such as a silicon nitride layer, can be deposited on the exposed top surface 2024 of the isolation column, the top surface 2034 of the reflective material layer, and the top surface 2044 of the first protective layer by plasma enhanced chemical vapor deposition (PECVD). The refractive material layer 205 covers the top surface 2024 of the isolation column, the top surface 2034 of the reflective material layer, and the top surface 2044 of the first protective layer.

[0074] like Figure 8 As shown, the isolation column 202, the reflective material layer 203 on the isolation column, the first protective layer 204 on the isolation column and the refractive material layer 205 can form an isolation structure 20, and form an accommodating space between two adjacent isolation structures 20, so that all the accommodating spaces can constitute an accommodating space array 2040.

[0075] In step S104 , quantum dots may be filled in the accommodating space array to form a quantum dot array, thereby obtaining the micro LED device.

[0076] According to an embodiment of the present disclosure, after obtaining the above-mentioned accommodating space array, quantum dots can be filled into the accommodating space array.

[0077] Furthermore, the accommodating space array includes multiple groups of accommodating spaces, each group of accommodating spaces including a first subspace, a second subspace, and a third subspace. Filling the accommodating space array with quantum dots includes at least one of the following: filling each first subspace with green quantum dots; filling each second subspace with red quantum dots. In some embodiments, each third subspace may be filled with blue quantum dots. In other embodiments, the micro-LED unit array emits blue light, and each third subspace may be filled with a transparent material or no material.

[0078] Reference Figure 2-13 ,in Figure 9 FIG. 2 shows a side view of green quantum dots 2061 and red quantum dots 2062 filled in the receiving space array 2040. Figure 8 For the sake of brevity and clarity, Figure 8 Only one group of accommodating spaces in the accommodating space array 2040 is shown, and the group of accommodating spaces includes a first subspace 2041, a second subspace 2042, and a third subspace 2043. It should be understood that the number of groups of accommodating spaces can be determined according to actual applications and is not limited here. Figure 8 ,like Figure 9 As shown, green quantum dots 2061 are filled into the first subspace 2041 of the accommodating space array 2040, and the green quantum dots are group II-VI quantum dots, and then cured by ultraviolet. And red quantum dots 2062 are filled into the second subspace 2042 of the accommodating space array 2040, and the red quantum dots are group II-VI quantum dots, and then cured by ultraviolet, to obtain the following: Figure 9 The structure shown. Figure 9 In the illustrated embodiment, the micro LED unit array emits blue light, and the third subspace 2043 is not filled with any material.

[0079] According to an embodiment of the present disclosure, after filling quantum dots in the accommodating space array to form a quantum dot array, the method may further include: providing an encapsulation layer on the quantum dot array and the isolation structure to encapsulate the quantum dot array and the isolation structure.

[0080] Furthermore, the encapsulation layer may include a first sub-encapsulation layer, and setting the encapsulation layer on the quantum dot array and the isolation structure may include: setting the first sub-encapsulation layer on the quantum dot array and the isolation structure; the first sub-encapsulation layer includes a second passivation layer and a filter film, and setting the first sub-encapsulation layer on the quantum dot array and the isolation structure may include: setting the second passivation layer on the quantum dot array and the isolation structure; and setting the filter film on the second passivation layer.

[0081] Furthermore, the encapsulation layer may also include a second sub-encapsulation layer, and setting the encapsulation layer on the quantum dot array and the isolation structure may also include: setting the second sub-encapsulation layer on the first sub-encapsulation layer; the second sub-encapsulation layer includes a microlens array, a sealant and a second protective layer, and setting the second sub-encapsulation layer on the first sub-encapsulation layer may include: setting a microlens array corresponding to the quantum dot array on the filter film; setting a sealant in the gaps of the microlens array; and setting a second protective layer on the microlens array and the sealant.

[0082] Reference Figure 2-13 ,in Figure 10 FIG. 2 shows a side view of a second passivation layer 207 and a filter film 208 disposed on the quantum dot array 2040 and the isolation structure 20. Figure 10 As shown, atomic layer deposition (ALD) can be used to deposit a second passivation layer 207 on the quantum dot array 2040 and the isolation structure 20. The material of the second passivation layer 207 can be, for example, aluminum oxide or silicon dioxide. The second passivation layer 207 can protect the quantum dots from moisture intrusion, thereby increasing the service life of the quantum dots. Then, an optical coating device can be used to coat a filter film 208 on the second passivation layer 207. For example, if the second passivation layer 207 is an aluminum oxide layer, the filter film 208 can be, for example, a silicon dioxide layer with a thickness equal to one-quarter of the wavelength of the light emitted by the micro LED unit. For example, when the micro-LED unit emits blue light to excite the green quantum dots 2061 and the red quantum dots 2062, the filter film 208 can enhance the reflection of the blue light, but does not affect the green light emitted by the blue light exciting the green quantum dots and the red light emitted by the blue light exciting the red quantum dots. That is, a portion of the blue light directly from the third subspace 2043 can be returned to the third subspace 2043, thereby weakening the blue light emitted through the third subspace 2043, and reflecting the blue light emitted from the green quantum dots 2061 and the red quantum dots 2062 back to the quantum dots, thereby increasing the blue light used to excite the quantum dots, and then increasing the emitted green and red light. Therefore, the filter film 208 makes the emitted red, green and blue light correct in color, thereby achieving better color gamut and brightness.

[0083] Reference Figure 2-13 ,in Figure 11 FIG. 2 shows a side view of a microlens array composed of microlenses 209 arranged on a filter film 208. Figure 11 As shown, a microlens 209 can be formed by placing a plastic sealant at a position corresponding to the quantum dot array on the filter film 208 and heating the plastic sealant to cause it to reflow. The microlens 209 can focus the light entering the microlens 209 and increase the light transmission.

[0084] Reference Figure 2-13 ,in Figure 12 FIG. 2 shows a side view of a sealant 210 disposed in the gaps of the microlens array. Figure 12 As shown, a sealant 211 can be placed in the gaps of the microlens array using photolithography. The sealant 211 can include, for example, photoresist, or any other suitable material. The sealant 211 has a predetermined thickness, so that the sealant 211 can cover a predetermined portion of the microlens 210. Thus, the sealant 211 fully surrounds the microlens 210, suppressing wide-angle light that could otherwise cause optical crosstalk and be emitted from the predetermined side portions of the microlens 211.

[0085] Reference Figure 2-13 ,in Figure 13 FIG. 2 shows a side view of a second protective layer 211 disposed on the microlens array and the sealant 210. Figure 13 As shown, a second protective layer 211 can be deposited on the microlens array and the sealant 210 by chemical vapor deposition. The second protective layer 211 can include, for example, magnesium fluoride, or any other suitable material. The second protective layer 211 is used to protect the microlens array and the sealant 210. Figure 12 The overall structure shown is protected from damage.

[0086] Thus, the micro LED device is prepared. Figure 13 Schematic diagram of a micro LED device 1 that has been fabricated according to an embodiment of the present disclosure.

[0087] The present disclosure also provides a micro LED device.

[0088] like Figure 2-13As shown, the micro LED device 1 includes: a micro LED structure 10, the micro LED structure 10 includes a micro LED chip 101, the micro LED chip 101 includes a micro LED unit array; an isolation structure array, wherein an accommodation space is formed between two adjacent isolation structures 20 in the isolation structure array, and all of the accommodation spaces constitute an accommodation space array 2040, and the accommodation space array 2040 corresponds to the micro LED unit array composed of the micro LED units 1011. Each isolation structure 20 in the isolation structure array includes: an isolation substructure, which is arranged on the surface of the light-emitting side of the micro LED structure and includes a reflective material layer 203 and a reflective material layer arranged on the reflective material layer. A first sub-protective layer 204 on the side wall of the material layer 203, the top surface of the isolation substructure includes the top surface 2034 of the reflective material layer 203 and the top surface 2044 of the first sub-protective layer 2045; a refractive material layer 205, which is arranged on the top surface of the isolation substructure, and the refractive material layer 205 covers the top surface 2034 of the reflective material layer 203 and the top surface 2044 of the first sub-protective layer 2045, wherein the difference between the refractive index of the refractive material layer 205 and the refractive index of the first sub-protective layer 2045 is greater than a preset value; a quantum dot array, the quantum dots in the quantum dot array are filled in the accommodation space in the accommodation space array 2040.

[0089] According to an embodiment of the present disclosure, the isolation substructure also includes an isolation column 202, the top surface of the isolation substructure also includes a top surface 2024 of the isolation column 202, the isolation column 202 is arranged on the surface of the light-emitting side of the micro-LED structure, the reflective material layer 203 is arranged on the side wall of the isolation column 202, and the first sub-protective layer 2045 is arranged on the side wall of the reflective material layer 203.

[0090] According to an embodiment of the present disclosure, the refractive material layer 205 is arranged on the top surface 2024 of the isolation column 202, the top surface 2034 of the reflective material layer 203 and the top surface 2044 of the first sub-protective layer 2045 and covers the top surface 2024 of the isolation column 202, the top surface 2034 of the reflective material layer 203 and the top surface 2044 of the first sub-protective layer 2045.

[0091] According to an embodiment of the present disclosure, the micro LED device 1 further includes an insulating layer 201 . The insulating layer 201 is disposed on the surface of the light-emitting side of the micro LED structure, and the isolation column 202 is disposed on the insulating layer 201 .

[0092] According to an embodiment of the present disclosure, each micro LED unit 1011 in the micro LED unit array includes a first semiconductor layer on the light-emitting side, the first semiconductor layer includes a first roughened surface 10111 , and the isolation layer 201 is disposed on the first roughened surface 10111 .

[0093] According to an embodiment of the present disclosure, the isolation layer 201 includes a plurality of sub-isolation layers, which are arranged in sequence from bottom to top on the surface of the light-emitting side of the micro-LED structure 10, wherein each of the plurality of sub-isolation layers has a preset thickness and a preset refractive index, and the total thickness of the plurality of sub-isolation layers is equal to half the wavelength of the light emitted by the micro-LED unit 1011, and the preset refractive index of each of the plurality of sub-isolation layers decreases in order from bottom to top of the plurality of sub-isolation layers.

[0094] According to an embodiment of the present disclosure, the reflective material layer 203 includes a metal layer, the metal layer includes a second roughened surface 2031 , and the second roughened surface 2031 includes a plurality of protrusions.

[0095] According to an embodiment of the present disclosure, the micro LED device 1 further includes a second sub-protective layer 2046, which is disposed on the insulating layer 201 in each accommodating space, and the second sub-protective layer 2046 and the first sub-protective layer 2045 are made of the same material and integrally constitute the first protective layer 204, the insulating layer 201 includes a plurality of sub-isolating layers, the plurality of sub-isolating layers being sequentially disposed from bottom to top on the surface of the light-emitting side of the micro LED structure 10, wherein the plurality of sub-isolating layers and the second sub-protective layer 2046 on the plurality of sub-isolating layers are disposed on the surface of the light-emitting side of the micro LED structure 10. 046 each has a preset thickness and a preset refractive index, the total thickness of the multiple sub-isolating layers is equal to one-quarter of the wavelength of the light emitted by the micro LED unit 1011, the preset thickness of the second sub-protective layer 2046 on the multiple sub-isolating layers is equal to one-quarter of the wavelength of the light emitted by the micro LED unit 1011, and the preset refractive index of each of the multiple sub-isolating layers and the second sub-protective layer 2046 on the multiple sub-isolating layers decreases in a bottom-up order of the multiple sub-isolating layers and the second sub-protective layer 2046 on the multiple sub-isolating layers.

[0096] According to an embodiment of the present disclosure, the preset value is greater than or equal to 1.

[0097] According to an embodiment of the present disclosure, the accommodating space array 2040 includes multiple groups of accommodating spaces, each group of accommodating spaces includes a first subspace 2041, a second subspace 2042 and a third subspace 2043, each first subspace 2041 is filled with green quantum dots 2061, and each second subspace 2042 is filled with red quantum dots 2062.

[0098] According to an embodiment of the present disclosure, the micro LED device 1 further includes an encapsulation layer, which is disposed on the quantum dot array and the isolation structure 20 .

[0099] According to an embodiment of the present disclosure, the encapsulation layer includes a first sub-encapsulation layer, which is arranged on the quantum dot array and the isolation structure 20. The first sub-encapsulation layer includes a second passivation layer 207 and a filter film 208. The second passivation layer 207 is arranged on the quantum dot array and the isolation structure 20; the filter film 208 is arranged on the second passivation layer 207.

[0100] According to an embodiment of the present disclosure, the encapsulation layer also includes a second sub-encapsulation layer, which is arranged on the first sub-encapsulation layer. The second sub-encapsulation layer includes a microlens array composed of microlenses 209, a sealant 210 and a second protective layer 211. The microlens array is arranged on the filter film 208 and corresponds to the quantum dot array. The sealant 210 is arranged in the gaps of the microlens array; the second protective layer 211 is arranged on the microlens array and the sealant 210.

[0101] It is worth noting that any relevant description of the micro LED device in the above-mentioned micro LED device preparation method (including but not limited to technical features and their functions, explanations, etc.) can be applied to the micro LED device disclosed in the present invention.

[0102] The present disclosure also provides a display device comprising the aforementioned micro LED device 1 .

[0103] The micro-LED device can be applied to flexible electronic devices to implement technologies such as augmented reality (AR), virtual reality (VR), extended reality (XR), and mixed reality (MR). For example, the micro-LED device can be the projection part of an electronic device, such as a projector or head-up display (HUD). For another example, the micro-LED device can also be the display part of an electronic device, such as a smartphone, smartwatch, laptop, tablet computer, dashcam, navigation system, head-mounted device, or any other device with a display screen.

[0104] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0105] It should be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned steps / processes does not mean the order of execution, and the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. In addition, the serial numbers of the embodiments of the present application mentioned above are only for description and do not represent the advantages and disadvantages of the embodiments.

[0106] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0107] The foregoing description is merely a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present disclosure shall be included within the scope of protection of the present disclosure.

Claims

1. A method for preparing a micro LED device, wherein: The method comprises: Obtaining a micro LED structure, wherein the micro LED structure includes a micro LED chip, and the micro LED chip includes a micro LED unit array; An array of spacer structures is provided on the surface of the light-emitting side of the micro-LED structure, wherein each spacer structure in the array of spacer structures comprises a reflective material layer and a first protective layer provided on a sidewall of the reflective material layer, and a top surface of the spacer structure comprises a top surface of the reflective material layer and a top surface of the first protective layer; A refractive material layer is disposed on the top surface of each of the spacer substructures, such that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer, wherein each spacer substructure and the corresponding refractive material layer form an isolation structure, all of the isolation structures constitute an isolation structure array, and accommodation spaces are formed between two adjacent isolation structures, all of the accommodation spaces constitute an accommodation space array, the accommodation space array corresponding to the micro LED unit array, wherein the difference between the refractive index of the refractive material layer and the refractive index of the first protective layer is greater than a preset value; The accommodating space array is filled with quantum dots to form a quantum dot array, thereby obtaining the micro LED device.

2. The method for preparing a micro LED device according to claim 1, wherein: Each of the isolating substructures in the isolating substructure array further includes an isolating column, and the top surface of the isolating substructure further includes the top surface of the isolating column. Arranging the isolating substructure array on the surface of the light-emitting side of the micro-LED structure includes: Disposing a first passivation layer having an array of through holes on the surface of the light-emitting side of the micro LED structure, such that each through hole in the array of through holes exposes a predetermined exposed portion of the surface of the light-emitting side of the micro LED structure and corresponds to a micro LED unit in the micro LED unit array, and the isolation column is formed between two adjacent through holes; providing a reflective material layer on the surface of the isolation column; providing a first protective layer on the reflective material layer; The reflective material layer and the first protective layer above the top of the isolation column are removed to expose the top surface of the isolation column, the top surface of the reflective material layer, and the top surface of the first protective layer.

3. The method for preparing a micro LED device according to claim 2, wherein: Providing a refractive material layer on the top surface of each of the spacer substructures so that the refractive material layer covers the top surface of the reflective material layer and the top surface of the first protective layer includes: A refractive material layer is disposed on the top surface of each of the isolation substructures, such that the refractive material layer covers the top surface of the isolation column, the top surface of the reflective material layer, and the top surface of the first protection layer.

4. The method for preparing a micro LED device according to claim 2, wherein: Before providing a first passivation layer having a through-hole array on the surface of the light-emitting side of the micro-LED structure, the method further includes: providing an isolation layer on the surface of the light-emitting side of the micro-LED structure, A first passivation layer having an array of through holes is provided on the surface of the light-emitting side of the micro-LED structure, so that each through hole in the through hole array exposes a preset exposed portion of the surface of the light-emitting side of the micro-LED structure and corresponds to a micro-LED unit in the micro-LED unit array, and an isolation column is formed between two adjacent through holes, including: providing a first passivation layer on the isolation layer, and opening a through hole array on the first passivation layer, so that each through hole in the through hole array exposes a preset exposed portion of the isolation layer and corresponds to the micro-LED unit in the micro-LED unit array, and an isolation column is formed between two adjacent through holes.

5. The method for preparing a micro LED device according to claim 4, wherein: Each micro LED unit in the micro LED unit array includes a first semiconductor layer on a light-emitting side. Before providing an insulating layer on the surface of the light-emitting side of the micro LED structure, the method further includes: roughening the surface of the first semiconductor layer to obtain a first roughened surface. Providing an insulating layer on the surface of the light-emitting side of the micro-LED structure includes: providing an insulating layer on the first roughened surface.

6. The method for preparing a micro LED device according to claim 4, wherein: The insulating layer includes a plurality of sub-insulating layers, and disposing the insulating layer on the surface of the light-emitting side of the micro-LED structure includes: The multiple sub-isolating layers are sequentially arranged from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein each of the multiple sub-isolating layers has a preset thickness and a preset refractive index, the total thickness of the multiple sub-isolating layers is equal to half the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the multiple sub-isolating layers decreases in order from bottom to top.

7. The method for preparing a micro LED device according to claim 2, wherein: Providing a reflective material layer on the surface of the isolation column includes: A reflective material layer is provided on the top and sidewall of the isolation column, and the reflective material layer on the sidewall of the isolation column is subjected to surface roughening treatment to obtain a second roughened surface.

8. The method for preparing a micro LED device according to claim 7, wherein: The reflective material layer includes a metal layer, and the reflective material layer is provided on the top and sidewall of the isolation column and the reflective material layer on the sidewall of the isolation column is subjected to surface roughening treatment, which includes: Depositing a metal layer of a preset thickness on the top and sidewalls of the isolation column so that the grains of the metal layer on the sidewalls of the isolation column have a tendency to grow laterally; The metal layer is annealed to form a plurality of protrusions on the surface of the metal layer on the sidewall of the isolation column.

9. The method for preparing a micro LED device according to claim 4, wherein: When providing a first protective layer on the reflective material layer, the method further comprises: providing the first protective layer on the exposed insulating layer, The isolation layer includes a plurality of sub-isolation layers, which are arranged in sequence from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein the plurality of sub-isolation layers and the first protective layer on the plurality of sub-isolation layers each have a preset thickness and a preset refractive index, the total thickness of the plurality of sub-isolation layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit, the preset thickness of the first protective layer on the plurality of sub-isolation layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-isolation layers and the first protective layer on the plurality of sub-isolation layers decreases in the bottom-up order of the plurality of sub-isolation layers and the first protective layer on the plurality of sub-isolation layers.

10. The method for preparing a micro LED device according to claim 1, wherein: The preset value is greater than or equal to 1.

11. The method for preparing a micro LED device according to claim 1, wherein: The accommodating space array includes multiple groups of accommodating spaces, each group of accommodating spaces includes a first subspace, a second subspace, and a third subspace, and filling quantum dots in the accommodating space array includes at least one of the following: Fill each first subspace with green quantum dots; Each second subspace is filled with red quantum dots.

12. The method for preparing a micro LED device according to claim 1, wherein: After filling quantum dots in the accommodating space array to form a quantum dot array, the method further includes: providing an encapsulation layer on the quantum dot array and the isolation structure.

13. The method for preparing a micro LED device according to claim 12, wherein: The encapsulation layer includes a first sub-encapsulation layer, and providing the encapsulation layer on the quantum dot array and the isolation structure includes: providing the first sub-encapsulation layer on the quantum dot array and the isolation structure; The first sub-packaging layer includes a second passivation layer and a filter film. Arranging the first sub-packaging layer on the quantum dot array and the isolation structure includes: arranging the second passivation layer on the quantum dot array and the isolation structure; and arranging the filter film on the second passivation layer.

14. The method for preparing a micro LED device according to claim 13, wherein: The encapsulation layer further includes a second sub-encapsulation layer, and providing the encapsulation layer on the quantum dot array and the isolation structure further includes: providing the second sub-encapsulation layer on the first sub-encapsulation layer; The second sub-packaging layer includes a microlens array, a sealant, and a second protective layer. Arranging the second sub-packaging layer on the first sub-packaging layer includes: arranging a microlens array corresponding to the quantum dot array on the filter film; arranging a sealant in the gaps of the microlens array; and arranging a second protective layer on the microlens array and the sealant.

15. The method for preparing a micro LED device according to claim 1, wherein: The micro LED structure also includes a driving substrate, which is bonded to the micro LED chip, or the driving substrate is not bonded to the micro LED chip. When the driving substrate is not bonded to the micro LED chip, after quantum dots are filled in the accommodating space array to form a quantum dot array, the method further includes: bonding the driving substrate to the micro LED chip.

16. The method for preparing a micro LED device according to claim 8, wherein: The material of the isolation column includes silicon dioxide, the material of the metal layer includes aluminum, the material of the first protective layer includes magnesium fluoride, and the material of the refractive material layer includes silicon nitride.

17. A micro LED device, wherein: The micro LED device comprises: A micro-LED structure comprising a micro-LED chip including a micro-LED unit array; an isolation structure array, wherein an accommodation space is formed between two adjacent isolation structures in the isolation structure array, and all of the accommodation spaces constitute an accommodation space array, the accommodation space array corresponding to the micro-LED unit array, each isolation structure in the isolation structure array comprising: an isolation substructure disposed on a surface of a light-emitting side of the micro-LED structure and comprising a reflective material layer and a first sub-protective layer disposed on a sidewall of the reflective material layer, wherein a top surface of the isolation substructure comprises a top surface of the reflective material layer and a top surface of the first sub-protective layer; and a refractive material layer disposed on a top surface of the isolation substructure and covering a top surface of the reflective material layer and a top surface of the first sub-protective layer, wherein a difference between a refractive index of the refractive material layer and a refractive index of the first sub-protective layer is greater than a preset value; A quantum dot array, wherein the quantum dots in the quantum dot array are filled in the accommodation spaces in the accommodation space array.

18. The micro LED device according to claim 17, wherein: The isolation substructure also includes an isolation column, the top surface of the isolation substructure also includes the top surface of the isolation column, the isolation column is arranged on the surface of the light-emitting side of the micro LED structure, the reflective material layer is arranged on the side wall of the isolation column, and the first sub-protective layer is arranged on the side wall of the reflective material layer.

19. The micro LED device according to claim 18, wherein: The refractive material layer is disposed on and covers the top surfaces of the isolation pillars, the reflective material layer, and the first sub-protective layer.

20. The micro LED device according to claim 18, wherein The micro LED device further includes an insulating layer, which is disposed on a surface of a light-emitting side of the micro LED structure, and the isolation column is disposed on the insulating layer.

21. The micro LED device according to claim 20, wherein: Each micro LED unit in the micro LED unit array includes a first semiconductor layer on a light-emitting side, the first semiconductor layer includes a first roughened surface, and the isolation layer is provided on the first roughened surface.

22. The micro LED device according to claim 20, wherein: The isolation layer includes a plurality of sub-isolating layers, which are sequentially arranged from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein each of the plurality of sub-isolating layers has a preset thickness and a preset refractive index, the total thickness of the plurality of sub-isolating layers is equal to half the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-isolating layers decreases in the order of the plurality of sub-isolating layers from bottom to top.

23. The micro LED device according to claim 18, wherein: The reflective material layer includes a metal layer, the metal layer includes a second roughened surface, and the second roughened surface includes a plurality of protrusions.

24. The micro LED device according to claim 20, wherein: The micro LED device further includes a second sub-protective layer, which is disposed on the insulating layer in each accommodation space, and the second sub-protective layer and the first sub-protective layer are made of the same material and integrally constitute the first protective layer. The isolation layer includes a plurality of sub-isolating layers, which are sequentially arranged from bottom to top on the surface of the light-emitting side of the micro-LED structure, wherein the plurality of sub-isolating layers and the second sub-protective layer on the plurality of sub-isolating layers each have a preset thickness and a preset refractive index, the total thickness of the plurality of sub-isolating layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit, the preset thickness of the second sub-protective layer on the plurality of sub-isolating layers is equal to one-quarter of the wavelength of the light emitted by the micro-LED unit, and the preset refractive index of each of the plurality of sub-isolating layers and the second sub-protective layer on the plurality of sub-isolating layers decreases in the bottom-up order of the plurality of sub-isolating layers and the second sub-protective layer on the plurality of sub-isolating layers.

25. The micro LED device according to claim 17, wherein: The preset value is greater than or equal to 1.

26. The micro LED device according to claim 17, wherein: The accommodating space array includes multiple groups of accommodating spaces, each group of accommodating spaces includes a first subspace, a second subspace and a third subspace, each first subspace is filled with green quantum dots, and each second subspace is filled with red quantum dots.

27. The micro LED device according to claim 17, wherein: The micro LED device further includes an encapsulation layer, which is disposed on the quantum dot array and the isolation structure.

28. The micro LED device according to claim 27, wherein: The encapsulation layer includes a first sub-encapsulation layer, which is arranged on the quantum dot array and the isolation structure. The first sub-encapsulation layer includes a second passivation layer and a filter film, and the second passivation layer is arranged on the quantum dot array and the isolation structure; the filter film is arranged on the second passivation layer.

29. The micro LED device according to claim 28, wherein: The encapsulation layer also includes a second sub-encapsulation layer, which is arranged on the first sub-encapsulation layer. The second sub-encapsulation layer includes a microlens array, a sealant, and a second protective layer. The microlens array is arranged on the filter film and corresponds to the quantum dot array. The sealant is arranged in the gaps of the microlens array; the second protective layer is arranged on the microlens array and the sealant.

30. A display device, wherein: The display device includes the micro LED device according to any one of claims 17 to 29.

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