Micro LED display substrate, manufacturing method therefor, and display apparatus

Abstract

Provided in the present disclosure are a Micro LED display substrate, a manufacturing method therefor, and a display apparatus. The Micro LED display substrate comprises a drive backplane, a plurality of Micro LED structures, and a plurality of color conversion structures, wherein the plurality of Micro LED structures is disposed at intervals on the drive backplane and is electrically connected to the drive backplane. The Micro LED structures are used for emitting light of a same color; one color conversion structure corresponds to one Micro LED structure, and each color conversion structure is located on the side facing away from the drive backplane of the corresponding Micro LED structure, and is used for converting the light emitted by the corresponding Micro LED structure into light of a set color, thus achieving the display of full-color images.

Description

Micro LED display substrate, manufacturing method thereof, and display device Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a Micro LED display substrate, a manufacturing method thereof, and a display device. Background Art

[0002] Augmented reality (AR) and virtual reality (VR) displays can use micro light-emitting diodes (Micro LEDs) as light-emitting devices to improve display brightness and image resolution. Currently, AR / VR displays typically use monochrome Micro LEDs to display monochrome images, resulting in poor display quality. Therefore, developing full-color images has become a hot topic of research.

[0003] Summary of the Invention

[0004] The present disclosure provides a Micro LED display substrate and a manufacturing method thereof, and a display device for achieving color display.

[0005] In a first aspect of the present disclosure, a Micro LED display substrate is provided, comprising:

[0006] Driver backplane;

[0007] Multiple Micro LED structures are spaced apart and electrically connected to the driver backplane; each Micro LED structure is configured to emit light of the same color;

[0008] Multiple color conversion structures, one color conversion structure corresponds to one Micro LED structure, and each color conversion structure is located on the side of the corresponding Micro LED structure away from the driving backplane, and is used to convert the light emitted by the corresponding Micro LED structure into light of a set color.

[0009] The Micro LED display substrate provided in the present disclosure further includes:

[0010] Multiple micro lenses are arranged at intervals; one micro lens corresponds to one Micro LED structure, and each micro lens is located on the side of the corresponding Micro LED structure away from the driving backplane.

[0011] In the Micro LED display substrate provided by the present disclosure, the color conversion structure is located between the micro lens and the Micro LED structure; the orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the micro lens on the driving backplane;

[0012] Micro LED display substrates also include:

[0013] a first insulating layer, located between the Micro LED structure and the color conversion structure, and covering each Micro LED structure;

[0014] The Micro LED structure includes a bottom surface and a top surface arranged opposite to each other, and a side surface located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively; the first insulating layer includes a first portion covering the top surface of the Micro LED structure, and a second portion connected to the first portion and covering the side surface of the Micro LED structure.

[0015] In the Micro LED display substrate provided by the present disclosure, the orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the first portion of the first insulating layer on the driving backplane;

[0016] Micro LED display substrates also include:

[0017] The light-blocking layer is located on the side of the first insulating layer facing away from the driving backplane, and fills the gap between two adjacent Micro LED structures and the gap between two adjacent color conversion structures; the surface of the light-blocking layer facing away from the driving backplane is connected to the surface of the adjacent color conversion structure facing away from the driving backplane to form a continuous surface; the microlens is located on the side of the color conversion structure and the light-blocking layer facing away from the driving backplane, and partially overlaps with the light-blocking layer.

[0018] In the Micro LED display substrate provided by the present disclosure, the color conversion structure completely covers the first portion of the first insulating layer and at least partially covers the second portion of the first insulating layer;

[0019] The microlens covers the surface of the color conversion structure and covers at least a portion of the surface of the first insulating layer not covered by the color conversion structure, so that the color conversion structure is wrapped within the microlens;

[0020] Micro LED display substrates also include:

[0021] The light blocking layer is filled in the gap between two adjacent micro lenses; along the direction perpendicular to the driving backplane, the height of the light blocking layer is greater than or equal to the height of the color conversion structure.

[0022] In the Micro LED display substrate provided by the present disclosure, the color conversion structure is located on the side of the micro lens away from the Micro LED structure;

[0023] The Micro LED structure includes a bottom surface and a top surface arranged opposite to each other, and side surfaces located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively; the microlens covers the top surface and at least part of the side surface of the Micro LED structure to at least partially enclose the Micro LED structure within the microlens.

[0024] In the Micro LED display substrate provided by the present disclosure, the surface of the micro lens facing away from the driving backplane is a flat surface or a curved surface.

[0025] The Micro LED display substrate provided in the present disclosure further includes:

[0026] The second insulating layer is located on the side of the microlens away from the driving backplane; the second insulating layer is in direct contact with the microlens and covers the microlenses and the gaps between the microlenses to form a flat surface on the side of the microlens away from the driving backplane.

[0027] In the Micro LED display substrate provided in the present disclosure, the Micro LED structure includes:

[0028] The first electrode is located on a side close to the driving back plate and is electrically connected to the driving back plate;

[0029] a first doped layer, located on a side of the first electrode facing away from the driving back plate;

[0030] a multi-quantum well layer, located on a side of the first doped layer facing away from the first electrode;

[0031] a second doped layer, located on a side of the multi-quantum well layer facing away from the first doped layer;

[0032] a third insulating layer located on a side of the second doped layer facing away from the driving backplate; the third insulating layer includes an opening exposing the second doped layer; the third insulating layer covers surfaces of the multi-quantum well layer, the first doped layer, and the first electrode, so as to enclose the multi-quantum well layer, the first doped layer, and the first electrode within the third insulating layer;

[0033] a second electrode located on a side of the third insulating layer facing away from the driving backplate; the second electrode covers a surface of the third insulating layer and is electrically connected to the second doped layer through the opening; the second electrode is also electrically connected to the driving backplate;

[0034] The Micro LED display backplane also includes:

[0035] The conductive filling layer is located in the gap between two adjacent Micro LED structures. The conductive filling layer is directly formed on the surface of the second electrode and is electrically connected to the second electrode.

[0036] In the Micro LED display substrate provided by the present disclosure, the height of the conductive filling layer is smaller than the height of the Micro LED structure along a direction perpendicular to the driving backplane.

[0037] In the Micro LED display substrate provided by the present disclosure, the color conversion structure includes a color conversion layer; the color conversion layer is used to convert at least part of the light emitted by the Micro LED structure into light of a set color.

[0038] In the Micro LED display substrate provided by the present disclosure, each color conversion structure further includes: a filter layer located on the side of the color conversion layer away from the Micro LED structure; the filter layer is used to filter out light with a color different from the color of the light emitted after color conversion by the color conversion layer.

[0039] In a second aspect of the present disclosure, a display device is provided, comprising any one of the above-mentioned Micro LED display substrates.

[0040] A third aspect of the present disclosure provides a method for manufacturing a Micro LED display substrate, comprising:

[0041] forming a plurality of Micro LED structures on a driving backplane;

[0042] A plurality of color conversion structures are formed on the side of the Micro LED structure facing away from the driver backplane; wherein, one color conversion structure corresponds to one Micro LED structure, and each color conversion structure is located on the side of the corresponding Micro LED structure facing away from the driver backplane.

[0043] The method provided in the present disclosure further includes:

[0044] A plurality of spaced microlenses are formed on a side of the color conversion structure facing away from the driver backplane; wherein one microlens corresponds to one Micro LED structure, and each microlens is located on the side of the corresponding Micro LED structure facing away from the driver backplane;

[0045] Before forming a plurality of color conversion structures on a side of the Micro LED structure facing away from the driving backplane, the method further includes:

[0046] A first insulating layer is deposited on the side of the multiple Micro LED structures facing away from the driver backplane; wherein the Micro LED structure includes a bottom surface and a top surface arranged opposite to each other, and a side surface located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively; the first insulating layer includes a first portion covering the top surface of the Micro LED structure, and a second portion connected to the first portion and covering the side surface of the Micro LED structure.

[0047] In the method provided in the present disclosure, a plurality of color conversion structures are formed on a side of the Micro LED structure facing away from the driver backplane, specifically comprising:

[0048] The orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the first portion of the first insulating layer on the driving backplane;

[0049] Before forming a plurality of spaced micro lenses on a side of the color conversion structure away from the driving backplane, the method further includes:

[0050] A light-blocking layer is formed on a side of the first insulating layer facing away from the driving backplane; the light-blocking layer fills a gap between two adjacent Micro LED structures and a gap between two adjacent color conversion structures; and a surface of the light-blocking layer facing away from the driving backplane is connected to a surface of an adjacent color conversion structure facing away from the driving backplane to form a continuous surface.

[0051] A plurality of spaced micro lenses are fabricated on the side of the color conversion structure facing away from the driving backplane, specifically including:

[0052] A microlens is formed on a side of the color conversion structure and the light blocking layer facing away from the driving backplane.

[0053] In the method provided in the present disclosure, a plurality of color conversion structures are formed on a side of the Micro LED structure facing away from the driver backplane, specifically comprising:

[0054] The color conversion structure completely covers the first portion of the first insulating layer and at least partially covers the second portion of the first insulating layer;

[0055] A plurality of spaced micro lenses are fabricated on the side of the color conversion structure facing away from the driving backplane, specifically including:

[0056] The microlens covers the surface of the color conversion structure and covers at least a portion of the surface of the first insulating layer not covered by the color conversion structure, so that the color conversion structure is wrapped within the microlens;

[0057] The method also includes:

[0058] A light blocking layer is formed in the gap between two adjacent micro lenses; wherein, along a direction perpendicular to the driving backplane, the height of the light blocking layer is greater than or equal to the height of the color conversion structure.

[0059] In the method provided in the present disclosure, the Micro LED structure includes a bottom surface and a top surface arranged opposite to each other, and side surfaces located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively;

[0060] Before forming a plurality of color conversion structures on a side of the Micro LED structure facing away from the driving backplane, the method further includes:

[0061] A plurality of spaced microlenses are formed on a side of the Micro LED structure facing away from the driver backplane. Each microlens corresponds to a Micro LED structure, and each microlens is located on the side of the corresponding Micro LED structure facing away from the driver backplane. The orthographic projection of the color conversion structure on the driver backplane and the orthographic projection of the Micro LED structure on the driver backplane are both located within the orthographic projection of the microlens on the driver backplane. The microlenses cover the top surface and at least a portion of the side surfaces of the Micro LED structure, so that the Micro LED structure is at least partially enclosed within the microlenses.

[0062] Multiple color conversion structures are formed on the side of the Micro LED structure facing away from the driver backplane, specifically including:

[0063] A color conversion structure is formed on the side of the microlens facing away from the driving backplane.

[0064] The beneficial effects of the present disclosure are as follows:

[0065] The present disclosure provides a Micro LED display substrate, a method for manufacturing the same, and a display device. The Micro LED display substrate includes a driver backplane, multiple Micro LED structures, and multiple color conversion structures. The multiple Micro LED structures are spaced apart and electrically connected to the driver backplane; each Micro LED structure is configured to emit light of the same color. Each color conversion structure corresponds to a Micro LED structure. Each color conversion structure is located on the side of the corresponding Micro LED structure facing away from the driver backplane and is configured to convert light emitted by the corresponding Micro LED structure into light of a set color, thereby achieving full-color image display. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments of the present disclosure. Obviously, the drawings introduced below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0067] FIG1 is a schematic diagram of a cross-sectional structure of a Micro LED display substrate according to an embodiment of the present disclosure;

[0068] FIG2 is a second schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0069] FIG3 is a third schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0070] FIG4 is a fourth schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0071] FIG5 is a fifth schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0072] FIG6 is a sixth schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0073] FIG7 is a seventh schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0074] FIG8 is an eighth schematic diagram of the cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0075] FIG9 is a ninth schematic diagram of a cross-sectional structure of a Micro LED display substrate provided in an embodiment of the present disclosure;

[0076] FIG10 is a schematic diagram of a process for manufacturing a microlens according to an embodiment of the present disclosure;

[0077] FIG11 is a flow chart of a method for manufacturing a Micr LED display substrate provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0078] In order to make the above-mentioned purposes, features and advantages of the present disclosure more obvious and easy to understand, the present disclosure will be further described below with reference to the accompanying drawings and examples. However, the example embodiments can be implemented in various forms and should not be understood as being limited to the embodiments set forth herein; on the contrary, these embodiments are provided to make the present disclosure more comprehensive and complete, and to fully convey the concepts of the example embodiments to those skilled in the art. The same figure marks in the figures represent the same or similar structures, and their repeated descriptions will be omitted. The words expressing position and direction described in the present disclosure are all explained using the accompanying drawings as examples, but changes can be made as needed, and all changes are included in the scope of protection of the present disclosure. The drawings of the present disclosure are only used to illustrate relative position relationships and do not represent true proportions.

[0079] Augmented reality (AR) and virtual reality (VR) displays can use micro light-emitting diodes (Micro LEDs) as light-emitting devices to improve display brightness and image resolution. Currently, AR / VR displays typically use monochrome Micro LEDs to display monochrome images, resulting in poor display quality. Therefore, developing full-color images has become a hot topic of research.

[0080] Figure 1 is one of the schematic diagrams of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure; Figure 2 is a second schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure; and Figure 3 is a third schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0081] In a first aspect of the embodiments of the present disclosure, a Micro LED display substrate is provided. As shown in FIG1 , the Micro LED display substrate includes a driving backplane 100, a plurality of Micro LED structures 200, and a plurality of color conversion structures 300. The plurality of Micro LED structures 200 are spaced apart and electrically connected to the driving backplane 100. The driving backplane 100 is provided with a driving circuit for driving the Micro LED structures 200 to emit light. In the embodiments of the present disclosure, each Micro LED structure 200 can emit light of the same color when driven by the driving backplane 100. The plurality of color conversion structures 300 are located on the side of the Micro LED structure 200 facing away from the driving backplane 100. One color conversion structure 300 corresponds to one Micro LED structure 200, and each color conversion structure 300 is located on the side of the corresponding Micro LED structure 200 facing away from the driving backplane 100, and is used to convert the light emitted by the corresponding Micro LED structure 200 into light of a set color.

[0082] In a specific implementation, the orthographic projection of each Micro LED structure 200 on the driver backplane 100 can be set to be located within the orthographic projection of the corresponding color conversion structure 300 on the driver backplane 100, so that more light emitted by the Micro LED structure 200 can be incident on the color conversion structure 300, thereby improving light utilization efficiency.

[0083] For example, in some embodiments, as shown in FIG2 , each Micro LED structure can emit ultraviolet (UV) light, and the multiple color conversion structures 300 can include a red color conversion structure 301, a green color conversion structure 302, and a blue color conversion structure 303. The red color conversion structure 301 is used to convert incident UV light into red light, the green color conversion structure 302 is used to convert incident UV light into green light, and the blue color conversion structure 303 is used to convert incident UV light into blue light. After passing through the color conversion structures 300, the emitted red, green, and blue light are mixed in different proportions to display a color image.

[0084] In some embodiments, as shown in FIG3 , each Micro LED structure 200 can emit blue light, and the multiple color conversion structures 300 can include a red color conversion structure 301 and a green color conversion structure 302. The red color conversion structure 301 is configured to convert incident blue light into red light, and the green color conversion structure 302 is configured to convert incident blue light into green light. The Micro LED display substrate further includes a blue light-transmitting structure 304. Each blue light-transmitting structure 304 corresponds to a Micro LED structure 200 and is located on the side of the corresponding Micro LED structure 200 facing away from the driver backplane 100. The blue light-transmitting structure 304 is configured to transmit incident blue light. After color conversion by the color conversion structure 300, the emitted red and green light are mixed with the blue light transmitted by the blue light-transmitting structure 304 in varying proportions, thereby displaying a color image. In specific implementations, the material of the blue light-transmitting structure 304 may include scattering particles to improve light uniformity, or the blue light-transmitting structure 304 may be replaced with a blue filter layer to filter out incident stray light, thereby emitting purer blue light. In some embodiments, the blue light-transmitting structure 304 may be omitted, and color images may be displayed directly using the blue light emitted by the Micro LED structure and the red and green light emitted by the color conversion structure. This is not limited here.

[0085] In a specific implementation, each Micro LED structure 200 can also be used to emit light of other colors and / or the color conversion structure 300 can also include a structure for converting the emitted light of the Micro LED structure 200 into more or fewer colors than red, green, and blue. As long as color image display can be achieved, there is no limitation here.

[0086] In some embodiments, the color conversion structure 300 includes a color conversion layer that is configured to convert light emitted from the Micro LED structure 200 into light of a predetermined color.

[0087] For example, in some embodiments, as shown in FIG2 , each Micro LED structure 200 can emit ultraviolet (UV) light, and the multiple color conversion structures 300 can include a red color conversion structure 301, a green color conversion structure 302, and a blue color conversion structure 303. The red color conversion structure 301 includes a red color conversion layer 311 for converting incident UV light into red light; the green color conversion structure 302 includes a green color conversion layer 312 for converting incident UV light into green light; and the blue color conversion structure 303 includes a blue color conversion layer 313 for converting incident UV light into blue light.

[0088] In some embodiments, as shown in FIG3 , each Micro LED structure can emit blue light, and the multiple color conversion structures 300 can include a red color conversion structure 301 and a green color conversion structure 302. The red color conversion structure 301 includes a red conversion layer 311 for converting incident blue light into red light; the green color conversion structure 302 includes a green color conversion layer 312 for converting incident blue light into green light. The Micro LED display substrate also includes a blue light-transmitting structure 304, one corresponding to each Micro LED structure. The blue light-transmitting structure 304 is located on the side of the corresponding Micro LED structure facing away from the driver backplane. The blue light-transmitting structure 304 includes a transparent layer 314 for transmitting incident blue light. The transparent layer 314 can be made of a resin matrix doped with scattering particles, which is not limited here. In specific implementations, the transparent layer can also be omitted, which is not limited here.

[0089] In the embodiment of the present disclosure, the color conversion layer 310 can be made of fluorescent materials or quantum dot (QD) materials. Quantum dot materials have high luminescence performance and color conversion efficiency, which can improve the utilization rate of light, obtain monochromatic light with higher purity, and improve the color gamut. The color of the light emitted by the quantum dot material is related to the size of the quantum dots, and the excitation light of the corresponding color can be obtained by controlling the size of the quantum dots. In specific implementation, the color conversion layer 310 can use a quantum dot resin with scattering particles, and form color conversion layers spaced apart from each other through a photolithography process. The scattering particles can be light scattering materials such as titanium dioxide, which are not limited here. The thickness of the color conversion layer 310 can be set to 1μm-5μm, specifically can be set to 2μm, which is not limited here.

[0090] In some embodiments, the color conversion structure 300 further includes a filter layer 320. The filter layer 320 is located on the side of the color conversion layer 310 facing away from the Micro LED structure 200. In a specific implementation, due to the conversion efficiency limitations of the color conversion layer 310, it cannot convert the color of all incident light. Therefore, the filter layer 320 is provided on the light-emitting side of the color conversion layer 310 to filter out light of a color different from the color of the light emitted after color conversion by the color conversion layer 310. For example, it filters out unconverted ultraviolet light or blue light emitted by the Micro LED structure 200, thereby making the color of the light emitted by the color conversion structure 300 purer. The filter layer 320 can be made of a filter material such as a color filter, and its thickness can be set to 0.5μm-2μm, specifically 1μm, which is not limited here.

[0091] For example, in some embodiments, as shown in FIG. 2 , each Micro LED structure may emit ultraviolet (UV) light, and the plurality of color conversion structures 300 may include a red color conversion structure 301 , a green color conversion structure 302 , and a blue color conversion structure 303 . The red color conversion structure 301 includes a red color conversion layer 311 and a red filter layer 321. The red color conversion layer 311 is configured to convert at least partially incident UV light into red light. The red filter layer 321 is configured to filter out UV light not converted by the red color conversion layer 311 and stray light other than red light, thereby enabling the red color conversion structure 301 to emit purer red light. The green color conversion structure 302 includes a green color conversion layer 312 and a green filter layer 322. The green color conversion layer 312 is configured to convert at least partially incident UV light into green light. The green filter layer 322 is configured to filter out UV light not converted by the green color conversion layer 312 and stray light other than green light. The blue color conversion structure 303 includes a blue color conversion layer 313 and a blue filter layer 323. The blue color conversion layer 313 is configured to convert at least partially incident UV light into blue light. The blue filter layer 323 is configured to filter out UV light not converted by the blue color conversion layer 312 and stray light other than blue light.

[0092] In some embodiments, as shown in FIG3 , each Micro LED structure can emit blue light. The multiple color conversion structures 300 may include a red color conversion structure 301 and a green color conversion structure 302. The red color conversion structure 301 includes a red color conversion layer 311 and a red filter layer 321. The red color conversion layer 311 is configured to convert at least partially incident blue light into red light. The red filter layer 321 is configured to filter out blue light not converted by the red color conversion layer 311 and stray light other than red light, thereby enabling the red color conversion structure 301 to emit purer red light. The green color conversion structure 302 includes a green color conversion layer 312 and a green filter layer 322. The green color conversion layer 312 is configured to convert at least partially incident blue light into green light. The green filter layer 322 is configured to filter out blue light not converted by the green color conversion layer 312 and stray light other than green light. The Micro LED display substrate also includes a blue light-transmitting structure 304. Each blue light-transmitting structure 304 corresponds to a Micro LED structure and is located on the side of the corresponding Micro LED structure facing away from the driver backplane. The blue light-transmitting structure 304 includes a transparent layer 314 and a blue filter layer 323. The transparent layer 314 is configured to transmit blue light, while the blue filter layer 323 is configured to filter out stray light other than blue light. In specific implementations, the transparent layer 314 and / or the blue filter layer 323 may be omitted, and this is not a limitation here.

[0093] FIG4 is a fourth schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0094] In some embodiments, as shown in FIG4 , the Micro LED display substrate further includes a plurality of spaced-apart micro lenses 400 . Each micro lens 400 corresponds to a Micro LED structure 200 , and each micro lens 400 is located on the side of the corresponding Micro LED structure 200 facing away from the driver backplane 100 . The micro lenses 400 can adjust the light emission angle and improve light extraction efficiency.

[0095] FIG5 is a fifth schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0096] In some embodiments, as shown in FIG5 , the color conversion structure 300 is located between the microlens 400 and the Micro LED structure 200. In a specific implementation, the orthographic projection of the color conversion structure 300 on the driving backplane 100 is located within the orthographic projection of the microlens 400 on the driving backplane 100. This allows more light emitted by the color conversion structure 300 to enter the microlens 400, thereby improving light utilization.

[0097] As shown in Figure 5, the Micro LED display substrate further includes a first insulating layer 500, located between the Micro LED structures 200 and the color conversion structures 300, and covering each Micro LED structure 200. The color conversion structures 300 are formed on the side of the first insulating layer 500 facing away from the Micro LED structures 200. The first insulating layer 500 provides insulation and protection for the Micro LED structures 200. The material of the first insulating layer 500 can be selected from insulating materials such as SiO2, which is not limited here.

[0098] As shown in Figure 5, the Micro LED structure 200 includes a bottom surface S1 and a top surface S2 disposed opposite each other, and a side surface S3 located between and connected to the bottom and top surfaces S1 and S2, respectively. The top surface S2 of the Micro LED structure 200 is located on the side of the bottom surface S1 facing away from the driver backplane 100, and generally serves as the light-emitting surface of the Micro LED structure 200, emitting light. The first insulating layer 500 includes a first portion 210 covering the top surface S2 of the Micro LED structure 200, and a second portion 520 connected to the first portion 210 and covering the side surface S3 of the Micro LED structure 200. In a specific implementation, the first insulating layer 500 can be formed entirely on the side of the Micro LED structure 200 facing away from the driver backplane 100 using a process such as chemical vapor deposition. The first insulating layer 500 also includes a third portion 530 formed in the gap between two adjacent Micro LED structures 200. The thickness of the first insulating layer 500 is between 100 nm and 500 nm, which is much smaller than the height of the Micro LED structure 200. After the first insulating layer 500 is deposited, the third portion 530 of the first insulating layer 500 cannot completely fill the gap between adjacent Micro LED structures 200, thereby forming a pit H. In a specific implementation, the thickness of the first insulating layer 500 can be set to 300 nm, which is not limited here.

[0099] In some embodiments, as shown in FIG5 , the Micro LED display substrate further includes: a second insulating layer 600 . The second insulating layer 600 is located on the side of the microlens 400 facing away from the driving backplane 100 . The second insulating layer 600 covers the surface of each microlens 400 and fills the gaps between each microlens 400 to form a flat surface on the side of the microlens 400 facing away from the driving substrate 100 , thereby playing a role in flattening and protecting. In a specific implementation, the material of the second insulating layer 600 can be an organic material, such as polyimide, acrylic, photoresist, etc., which is not limited here. The height of the second insulating layer 600 is greater than the height of the microlens 400. In a specific implementation, the distance h1 between the surface of the second insulating layer 600 facing away from the driving backplane 100 and the highest point of the top of the microlens 400 is between 0.1 μm and 2 μm, and can be specifically set to 0.8 μm, which is not limited here.

[0100] FIG6 is a sixth schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure; FIG7 is a seventh schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0101] In the embodiment shown in FIG5 , the Micro LED structure 200 can be a horizontal structure or a vertical structure. The P electrode and the N electrode of the horizontal Micro LED structure 200 are located on the same side of the Micro LED structure 200, and the P electrode and the N electrode of the vertical Micro LED structure 200 are located on opposite sides of the Micro LED structure 200. FIG6 and FIG7 illustrate the specific structure of the Micro LED display substrate in the embodiment shown in FIG5 using the vertical Micro LED structure 200 as an example. As shown in FIG6 and FIG7 , the Micro LED structure 200 includes a first electrode 210, a first doping layer 220, a multi-quantum well layer (MQW) 230, a second doping layer 240, a third insulating layer 250, and a second electrode 260 stacked in a direction away from the driving backplane 100.

[0102] The first electrode 210 is electrically connected to the driving backplane 100. In a specific implementation, the first electrode 210 may include a conductive layer that directly contacts the driving backplane 100 and a bonding layer located on the side of the conductive layer facing away from the driving backplane 100. The bonding layer can improve the connection between the Micro LED structure 200 and the driving backplane 100, enhancing mechanical, electrical, and thermal properties.

[0103] The first doped layer 220 is electrically connected to the first electrode 210, and the second doped layer 240 is electrically connected to the second electrode 260. The first doped layer 220 can be a P-type semiconductor layer (or an N-type semiconductor layer), and the second doped layer 220 can be an N-type semiconductor layer (or a P-type semiconductor layer). In this embodiment, the first doped layer 220 is a P-type semiconductor layer, and its material can be selected from Mg-doped GaN. Its thickness can be set to between 100nm and 500nm, specifically 220nm, which is not limited here. The second doped layer 240 is an N-type semiconductor layer, and its material can be selected from Si-doped GaN. Its thickness can be set to between 10nm and 100nm, specifically 30nm, which is not limited here. The first electrode 210 is a P-electrode, and the first electrode 210 includes a stacked conductive layer and a bonding layer, wherein the conductive layer can be a single-layer structure or a multi-layer structure in which multiple conductive film layers are stacked, and the bonding layer can be a single-layer structure or a multi-layer structure in which multiple conductive film layers are stacked, which is not limited here. The thickness of the first electrode 210 can be set between 500nm and 3000nm. In a specific implementation, the conductive layer of the first electrode 210 can include multiple conductive film layers such as ITO, Cr, Pt, Ti, Au, SnPt, Au, SnPt, and Au stacked in a direction away from the driving backplane 100, and the thickness of each conductive film layer is set to 138nm, 8.5nm, 36.5nm, 12.2nm, 118.1nm, 87.6nm, 102.8nm, 113.7nm, and 133.2nm, respectively. The bonding layer of the first electrode 210 can include multiple conductive film layers such as Ti, Pt, and Ti stacked in a direction away from the driving backplane 100, and the thickness of each conductive film layer is set to 7.0nm, 5.7nm, and 20nm, respectively. The second electrode 260 is an N-electrode. The second electrode 260 can be a single-layer structure or a multi-layer structure in which multiple conductive film layers are stacked, which is not limited here. In a specific implementation, the conductive layer of the first electrode 210 may include multiple film layers such as Cr and Pt stacked in a direction away from the driving backplane 100, wherein the thickness of Cr can be set to 10nm~50nm, specifically 30nm, and the thickness of Pt can be set to 100nm-500nm, specifically 270nm, which is not limited here.

[0104] The multi-quantum well layer 230 is located between the first doped layer 220 and the second doped layer 230. Electrons from the N-type semiconductor layer recombine with holes from the P-type semiconductor layer in the quantum well layer 230, generating photons and thus emitting light. In a specific implementation, the multi-quantum well layer 230 can be a periodic structure of alternating InGaN and GaN layers. The total thickness of the multi-quantum well layer 230 is between 50 nm and 500 nm, and can be specifically set to 130 nm, although this is not limited here.

[0105] The third insulating layer 250 is located on the side of the second doped layer 240 facing away from the driving backplate 100. The third insulating layer 250 includes an opening exposing the second doped layer 240 to facilitate connection between the second electrode 260 and the second doped layer 240. The third insulating layer 250 covers the surfaces of the multi-quantum well layer 230, the first doped layer 220, and the first electrode 210, thereby enclosing the multi-quantum well layer 230, the first doped layer 220, and the first electrode 210 within the third insulating layer 250, providing insulation and protection to prevent unnecessary electrical contact with the second electrode 260. The third insulating layer 250 covers the surfaces of the multi-quantum well layer 230, the first doped layer 220, and the first electrode 210. Specifically, the third insulating layer 250 covers the surfaces of the multi-quantum well layer 230, the first doped layer 220, and the first electrode 210 that are not covered by other film layers, such as the side surfaces of the multi-quantum well layer 230, the first doped layer 220, and the first electrode 210 in Figure 5, to provide protection. The second electrode 260 is located on a side of the third insulating layer 250 facing away from the driving backplane 100. The second electrode 260 covers the surface of the third insulating layer 250 and is electrically connected to the second doped layer 240 through an opening in the third insulating layer 250. The second electrode 260 is also electrically connected to the driving backplane 100. The third insulating layer 250 can be made of an insulating material such as silicon dioxide, and its thickness can be set to 100 nm to 500 nm, specifically 300 nm, which is not limited here.

[0106] In some embodiments, the Micro LED structure 200 may further include a superlattice layer between the N-type semiconductor layer and the multi-quantum well layer to improve the quality of the epitaxial layer. The superlattice layer may comprise a periodically interlaced arrangement of InGaN and GaN layers. The total thickness of the superlattice layer may be set to 10 nm to 200 nm, specifically 70 nm. The superlattice layer may also employ other structures, which are not limited herein.

[0107] In the embodiment shown in Figures 6 and 7, the first doped layer 220, the multi-quantum well layer 230, and the second doped layer 240 constitute an epitaxial structure. The epitaxial structure can be fabricated on a separate substrate by processes such as deposition and etching, and then transferred to the driving backplane 100 and electrically connected to the driving backplane 100 via the first electrode 210. Then, on the side of the epitaxial structure facing away from the driving backplane 100, a layer of insulating material 25 is deposited to cover the entire surface by a deposition process such as chemical vapor deposition. The third insulating layer 250 of each Micro LED structure 200 is located in the insulating material layer 25. After the insulating material layer 25 is formed, an opening is opened in the third insulating layer 250 of each Micro LED structure 200 to expose the second doped layer 240, facilitating subsequent connection to the second electrode 260. After openings are formed in the third insulating layer 250, a second electrode material layer 26 is formed entirely on the side of the insulating material layer 25 facing away from the driver backplane 100 through a deposition process such as sputtering deposition. The second electrode material layer 26 is electrically connected to the second doped layer 240 and the driver backplane 100 through the openings in the insulating material layer 25. The second electrode 260 of each Micro LED structure 200 is located in the second electrode material layer 26, covering the surface of the third insulating layer 250 of the Micro LED structure 200. The second electrodes 260 of each Micro LED structure 200 are interconnected to form a common electrode structure.

[0108] Since the epitaxial structure is manufactured through an etching process, due to the influence of the etching deviation, the width of the epitaxial structure gradually decreases in the direction from the first doped layer 220 to the second doped layer 240, as shown in Figures 6 and 7, so that the cross-sectional shape of the epitaxial structure forms a structure that is approximately trapezoidal, and the angle between the waist of the trapezoid (in the cross-section shown in Figures 6 and 7, the upper surface and the lower surface of the epitaxial structure are straight lines in the cross-section, and the line L between the endpoints on the same side of the straight lines formed by the upper surface and the lower surface is the waist of the trapezoid) and the lower base of the trapezoid (in the cross-section shown in Figures 6 and 7, the lower surface of the epitaxial structure is a straight line in the cross-section) is between 30° and 75°, specifically 63°, which is not limited here.

[0109] In some embodiments, as shown in FIG6 , the orthographic projection of the color conversion structure 300 on the driving backplane 100 is located within the orthographic projection of the first portion 510 of the first insulating layer 500 on the driving backplane 100 . The color conversion structure 300 is disposed only on the surface of the first portion 510 of the first insulating layer 500 . The Micro LED display substrate further includes:

[0110] The light-blocking layer 700 is located on the side of the first insulating layer 500 facing away from the driver backplane 100 and fills the gap between two adjacent Micro LED structures 200 (in the recess H formed by the first insulating layer 500) and the gap between two adjacent color conversion structures 300 to prevent color mixing. The surface of the light-blocking layer 700 facing away from the driver backplane 100 is connected to the surface of the adjacent color conversion structure 300 facing away from the driver backplane 100 to form a continuous surface. The microlens 400 is located on the side of the color conversion structure 300 and the light-blocking layer 700 facing away from the driver backplane 100 and partially overlaps with the light-blocking layer 700. The light-blocking layer 700 can be made of materials used to make black matrices (BMs) in related art, or other light-blocking materials, which are not limited here.

[0111] In the embodiment shown in Figure 6, the spacing between the microlenses 400 (the minimum distance between the orthographic projections of the microlenses 400 on the driving backplane 100) can be set to 0.1 μm-5 μm. Specifically, it can be set to 0.5 μm. The width (diameter) of the orthographic projection of each microlens 400 on the driving backplane 100 can be set to 1 μm-5 μm. Specifically, it can be set to 3.5 μm. The height of each microlens 400 (the distance h2 from the top of the microlens 400 to the surface of the color conversion structure 300 facing away from the driving backplane 100) can be set to 1 μm-5 μm. Specifically, it can be set to 2.8 μm. The orthographic projection of the first doping layer 220 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100. The width (diameter) of the orthographic projection of the first doping layer 220 on the driving backplane 100 can be set to 1 μm-5 μm, specifically, it can be set to 2.5 μm, which is not limited here. The orthographic projection of the second doped layer 240 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100. The width (diameter) of the orthographic projection of the second doped layer 240 on the driving backplane 100 can be set to 1μm-5μm, specifically 1.2μm. The total height of the epitaxial structure composed of the first doped layer 220, the multi-quantum well layer 230 and the second doped layer 240 of the Micro LED structure 200 can be set to 1μm-5μm, specifically 3.6μm. In a specific implementation, the distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the first doped layer 220 of the Micro LED structure 200 on the driving backplane 100 can be set to 0.1μm-5μm, specifically 0.6μm. The distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the second doping layer 240 of the Micro LED structure 200 on the driving backplane 100 can be set to 1 μm-5 μm, specifically 1.4 μm.

[0112] In the embodiment shown in FIG6 , the color conversion structure 300 may include a color conversion layer 310 and a filter layer 320. The orthographic projections of the color conversion layer 310 and the filter layer 320 on the driver backplane 100 are both located within the orthographic projections of the microlenses 400 on the driver backplane 100. The orthographic projections of the second doped layer 240 of the Micro LED structure 200 on the driver backplane 100 are located within the orthographic projections of the color conversion layer 310 on the driver backplane 100, and the orthographic projections of the second doped layer 240 of the Micro LED structure 200 on the driver backplane 100 are also located within the orthographic projections of the filter layer 320 on the driver backplane 100. This allows more light emitted from the Micro LED structure 200 to enter the color conversion structure 300, thereby improving light utilization. In specific implementations, the orthographic projections of the color conversion layer 310 and the filter layer 320 on the driver backplane 100 can be configured to completely overlap, although this is not a limitation herein. The width (diameter) of the orthographic projection of the color conversion layer 310 on the driving backplane 100 can be set to 1μm-5μm, specifically 2μm, and the width (diameter) of the orthographic projection of the filter layer 320 on the driving backplane 100 can be set to 1μm-5μm, specifically 2μm, which is not limited here.

[0113] In the embodiment shown in FIG. 6 , the color conversion structure 300 may include only the color conversion layer 310 , which is not limited herein.

[0114] In some embodiments, as shown in FIG7 , the color conversion structure 300 completely covers the first portion 510 of the first insulating layer 500 and at least partially covers the second portion 520 of the first insulating layer 500. This increases the planar size of the color conversion structure 300, improves the pixel aperture ratio, and further increases the amount of light emitted from the Micro LED structure 200 and incident on the corresponding color conversion structure 300, thereby improving light utilization. In a specific implementation, after the color conversion structure 300 is formed on the side of the first insulating layer 500 facing away from the Micro LED structure 200, each microlens 400 can be directly formed, so that the microlens 400 covers the surface of the corresponding color conversion structure 300 and at least partially covers the surface of the first insulating layer 500 not covered by the color conversion structure 300. This allows the color conversion structure 300 to be enclosed within the microlens 400, ensuring that all light emitted from the color conversion structure 300 is incident on the microlens 400, thereby improving light utilization.

[0115] During specific fabrication, after forming the color conversion structure 300 on the side of the first insulating layer 500 facing away from the Micro LED structure 200, a microlens material layer can be formed directly on the side of the color conversion structure 300 facing away from the driver backplane 100 using a process such as chemical vapor deposition to completely cover the entire surface. The microlens material layer can then be etched to form a plurality of spaced microlenses 40. After forming the microlenses 400, the gaps between adjacent microlenses 400 can be filled with a light-blocking material to form a light-blocking layer 700 to prevent color mixing. In specific implementations, the height of the light-blocking layer 700, perpendicular to the driver backplane 100, is greater than or equal to the height of the color conversion structure 300, thereby further preventing color mixing. Because the color conversion structure 300 is enclosed within the microlenses 400, light emitted laterally from the color conversion structure 300 is reflected at the interface between the sidewalls of the microlenses 400 and the light-blocking layer 700, redirected, and then emitted toward the top of the microlenses 400, thereby improving light direction and efficiency.

[0116] In the embodiment shown in FIG7 , the spacing between the microlenses 400 (the minimum distance between the orthographic projections of the microlenses 400 on the driving backplane 100) can be set to 0.1 μm-5 μm. Specifically, it can be set to 0.3 μm. The width (diameter) of the orthographic projection of each microlens 400 on the driving backplane can be set to 1 μm-5 μm. Specifically, it can be set to 3.5 μm. The distance h2 from the top of each microlens 400 to the surface of the color conversion structure 300 facing away from the driving backplane 100 can be set to 1 μm-5 μm. Specifically, it can be set to 2.8 μm. The orthographic projection of the first doping layer 220 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100. The width (diameter) of the orthographic projection of the first doping layer 220 on the driving backplane 100 can be set to 1 μm-5 μm, specifically, it can be set to 2.5 μm. The orthographic projection of the second doped layer 240 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100. The width (diameter) of the orthographic projection of the second doped layer 240 on the driving backplane 100 can be set to 1μm-5μm, specifically 1.2μm. The total height of the epitaxial structure composed of the first doped layer 220, the multi-quantum well layer 230 and the second doped layer 240 of the Micro LED structure 200 can be set to 1μm-5μm, specifically 3.6μm. In a specific implementation, the distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the first doped layer 220 of the Micro LED structure 200 on the driving backplane 100 can be set to 0.1μm-5μm, specifically 0.6μm. The distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the second doping layer 240 of the Micro LED structure 200 on the driving backplane 100 can be set to 1 μm-5 μm, specifically 1.4 μm.

[0117] The film layers not mentioned in the embodiment shown in FIG. 7 can be arranged with reference to the corresponding film layers in FIG. 6 , and are not described in detail here.

[0118] FIG8 is an eighth schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0119] In some embodiments, as shown in FIG. 8 , the color conversion structure 300 is located on a side of the microlens 400 facing away from the Micro LED structure 200 .

[0120] The Micro LED structure 200 includes a bottom surface S1 and a top surface S2 disposed opposite each other, and a side surface S3 located between the bottom surface S1 and the top surface S2 and connected to the bottom surface S1 and the top surface S2, respectively. The microlens 400 covers the top surface S2 and at least a portion of the side surface S3 of the Micro LED structure 200, thereby at least partially enclosing the Micro LED structure 200 within the microlens 400. In a specific implementation, the light emitted by the Micro LED structure 200 exhibits a Lambertian distribution. Part of the light emitted by the Micro LED structure 200 propagates perpendicularly to the driving backplane 100, and part propagates to the sides of the Micro LED structure 200. Because the Micro LED structure 200 is at least partially enclosed within the microlens 400, the light emitted from the Micro LED structure 200 to the sides can be reflected by the sidewalls of the microlens 400, thereby improving the light output direction, allowing more light to propagate perpendicularly to the driving backplane 100 and improving light utilization. Furthermore, the microlens 400 is usually made of insulating material. By wrapping the Micro LED structure 200 with the microlens 400, the use of an insulating layer can be reduced, which is beneficial for reducing the thickness of the Micro LED display substrate and reducing the production cost.

[0121] In some embodiments, as shown in FIG8 , the Micro LED display substrate further includes a second insulating layer 600 . The second insulating layer 600 is located on the side of the microlenses 400 facing away from the driving backplane 100 and between the color conversion structure 300 and the microlenses 400 . The second insulating layer 600 covers the surface of each microlens 400 and fills the gaps between them, forming a flat surface on the side of the microlenses 400 facing away from the driving substrate 100 . This provides flatness and protection, facilitating the subsequent fabrication of the color conversion structure 300 . In specific implementations, the second insulating layer 600 can be made of an organic material, such as polyimide, acrylic, or photoresist, though this is not a limitation. The height of the second insulating layer 600 is greater than that of the microlenses 400 . In specific implementations, the distance h1 between the surface of the second insulating layer 600 facing away from the driving backplane 100 and the highest point of the microlenses 400 is between 0.1 μm and 2 μm, and can be set to 0.8 μm, though this is not a limitation.

[0122] In some embodiments, as shown in FIG8 , the Micro LED display substrate further includes a light blocking layer 700. The light blocking layer 700 is located in the gaps between adjacent color conversion structures 300 to prevent color mixing. In a specific implementation, the orthographic projections of the color conversion structures 300 on the driving backplane 100 are located within the orthographic projections of the microlenses 400 on the driving backplane 100. The orthographic projections of the light blocking layer 700 on the driving backplane 100 cover the gaps between the orthographic projections of adjacent microlenses 400 on the driving backplane 100.

[0123] FIG9 is a ninth schematic diagram of the cross-sectional structure of the Micro LED display substrate provided in an embodiment of the present disclosure.

[0124] In the embodiment shown in FIG8 , the Micro LED structure 200 can be a horizontal structure or a vertical structure. In the horizontal Micro LED structure 200, the P electrode and N electrode are located on the same side of the Micro LED structure 200, while in the vertical Micro LED structure 200, the P electrode and N electrode are located on opposite sides of the Micro LED structure 200. FIG9 illustrates the specific structure of the Micro LED display substrate in the embodiment shown in FIG8 using a vertical Micro LED structure 200 as an example. As shown in FIG9 , the Micro LED structure 200 includes a first electrode 210, a first doped layer 220, a multi-quantum well layer (MQW) 230, a second doped layer 240, a third insulating layer 250, and a second electrode 260, stacked along one side away from the driving backplane 100. In specific implementations, the specific structure of the Micro LED structure 200 is the same as that of the embodiments shown in FIG6 and FIG7 , and can be configured with reference to FIG6 and FIG7 , and will not be further described here.

[0125] In the embodiment shown in FIG9 , the spacing between the microlenses 400 (the minimum distance between the orthographic projections of each microlens 400 on the driving backplane 100) can be set to 0.1 μm-5 μm. Specifically, it can be set to 0.3 μm. The width (diameter) of the orthographic projection of each microlens 400 on the driving backplane 100 can be set to 1 μm-5 μm. Specifically, it can be set to 3.5 μm. The distance h3 from the top of each microlens 400 to the surface of the second electrode 260 facing away from the driving backplane 100 can be set to 1 μm-5 μm. Specifically, it can be set to 2.8 μm. The orthographic projection of the first doping layer 220 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100, and the width (diameter) of the orthographic projection of the first doping layer 220 on the driving backplane 100 can be set to 1 μm-5 μm. Specifically, it can be set to 2.5 μm. The orthographic projection of the second doping layer 240 of the Micro LED structure 200 on the driving backplane 100 is located within the orthographic projection of the corresponding microlens 400 on the driving backplane 100. The width (diameter) of the orthographic projection of the second doping layer 240 on the driving backplane 100 can be set to 1μm-5μm. Specifically, it can be set to 1.2μm. The total height of the epitaxial structure composed of the first doping layer 220, the multi-quantum well layer 230 and the second doping layer 240 of the Micro LED structure 200 can be set to 1μm-5μm, specifically, it can be set to 3.6μm. In a specific implementation, the distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the first doping layer 220 of the Micro LED structure 200 on the driving backplane 100 can be set to 0.1μm-5μm, specifically, it can be set to 0.6μm. The distance between the edge of the orthographic projection of the microlens 400 on the driving backplane 100 and the edge of the orthographic projection of the second doping layer 240 of the Micro LED structure 200 on the driving backplane 100 can be set to 1 μm-5 μm, specifically 1.4 μm.

[0126] In the embodiment shown in FIG9 , the color conversion structure 300 may include a color conversion layer 310 and a filter layer 320. The orthographic projections of the color conversion layer 310 and the filter layer 320 on the driving backplane 100 are both located within the orthographic projections of the microlenses 400 on the driving backplane 100. The orthographic projections of the Micro LED structure 200 on the driving backplane 100 are located within the orthographic projections of the color conversion layer 310 and the filter layer 320, respectively. This allows more light emitted by the Micro LED structure 200 to enter the color conversion structure 300, improving light utilization. In specific implementations, the orthographic projections of the color conversion layer 310 and the filter layer 320 on the driving backplane 100 can be configured to completely overlap, although this is not a limitation herein. The width (diameter) of the orthographic projection of the color conversion layer 310 on the driving backplane 100 can be set to 1 μm-5 μm, specifically 3 μm. The width (diameter) of the orthographic projection of the filter layer 320 on the driving backplane 100 can be set to 1 μm-5 μm, specifically 3 μm, without limitation herein. The width of the light blocking layer 700 is adapted to the width of the gap between adjacent color conversion structures 300 and can range from 0.5 μm to 2 μm, without limitation herein.

[0127] The film layers not mentioned in the embodiment shown in FIG. 9 can be arranged with reference to the corresponding film layers in FIG. 6 , and are not described in detail here.

[0128] FIG10 is a schematic diagram of a process for manufacturing a microlens according to an embodiment of the present disclosure.

[0129] In some embodiments, as shown in Figures 4-9 , the side of the microlens 400 facing away from the driver substrate 100 can be configured as a curved surface. In a specific implementation, the curved surface can be a spherical surface. As shown in Figure 10 , forming the spherical microlens 400 can include the following steps: First, a microlens material layer 40 is deposited on the driver backplane 100 that has completed the previous process (having formed the Micro LED structure 200 or the color conversion structure 300), and a photoresist layer 1 is applied to the side of the microlens material layer 40 facing away from the driver backplane 100. The photoresist layer 1 is then etched to form a plurality of etched patterns 11 corresponding to the microlenses 400. The orthographic projections of the etched patterns 11 on the driver backplane 100 overlap the orthographic projections of the Micro LED structure 200 on the driver backplane 100. The distance between the edge of the orthographic projection of the etched pattern 11 on the driver backplane 100 and the edge of the orthographic projection of the Micro LED structure 200 on the driver backplane 100 is 1 μm-10 μm to reserve sufficient etching margin. After the etched pattern 11 is formed, the etched pattern 11 is heated through a thermal reflow process so that the etched pattern 11 softens and deforms at high temperature to form a plurality of spherical patterns 12. The heating temperature needs to be higher than the glass softening temperature of the etched pattern 11, usually between 100°C and 110°C or between 110°C and 120°C, which is not limited here. After the spherical pattern 12 is formed, the spherical pattern 12 and the microlens material layer 40 are etched simultaneously through a dry etching process. During the etching process, the microlens material layer 40 corresponding to the area not covered by the spherical pattern 12 is preferentially etched compared to the microlens material layer 40 corresponding to the area covered by the spherical pattern 12. As the etching proceeds, the spherical pattern 12 is ashed during the etching process, and the thinner area of ​​the spherical pattern 12 preferentially exposes the microlens material layer 40 that it blocks, and the exposed microlens material layer 40 is then etched. Finally, the spherical pattern 12 is completely ashed and removed from the surface of the microlens material layer 40. Multiple spherical surfaces corresponding to the spherical pattern 12 are formed on the microlens material layer 40. Further etching of the microlens material layer 40 yields multiple spherical microlenses 400 spaced apart from one another. In specific implementations, the surfaces of the microlenses 400 may also be curved surfaces of other shapes, which are not limited here.

[0130] In some embodiments, the side of the microlens 400 facing away from the driving substrate 100 can be set to a flat surface. The flat microlens 400 does not require a thermal reflow process during production. After the etching pattern 11 is formed, the microlens material layer 40 can be etched using a dry etching process, which will not be described in detail here.

[0131] In some embodiments, as shown in Figures 6, 7, and 9, the Micro LED display substrate further includes a conductive filling layer 800. The conductive filling layer 800 is located in the gap between two adjacent Micro LED structures 200. In a specific implementation, the conductive filling layer 800 is directly formed on the surface of the second electrode 260 and is electrically connected to the second electrode 260. The conductive filling layer 800 can serve as an auxiliary electrode to increase the cross-sectional area of ​​the common electrode structure formed by interconnecting the second electrodes 260 of each Micro LED structure 200, thereby reducing the surface resistance. In addition, since the second electrode material layer 26 where the second electrode 260 is located is relatively thin, it is easy to break at the corners and steps of the film layer. By connecting the second electrodes 260 of two adjacent Micro LED structures 200 through the conductive filling layer 800, the risk of breaking the common electrode structure can be reduced. In the embodiments shown in Figures 6 and 7 , after forming the second electrode material layer 26 where the second electrode 260 is located, a conductive filling layer 800 can be deposited in the gap between two adjacent Micro LED structures 200, so that the conductive filling layer 800 is directly formed on the surface of the second electrode 260. A first insulating layer 500 can then be formed on the side of the second electrode 260 and the conductive filling layer 800 facing away from the drive substrate 100. In the embodiment shown in Figure 9 , after forming the second electrode material layer 26 where the second electrode 260 is located, a conductive filling layer 800 can be deposited in the gap between two adjacent Micro LED structures 200, so that the conductive filling layer 800 is directly formed on the surface of the second electrode 260. A microlens 400 can then be formed on the side of the second electrode 260 and the conductive filling layer 800 facing away from the drive substrate 100. This is not limited herein.

[0132] In a specific implementation, along a direction perpendicular to the driving backplane 100 , the height of the conductive filling layer 800 is smaller than the height of the Micro LED structure 200 , so as to avoid cost increase caused by filling too much conductive material.

[0133] In a second aspect of the embodiments of the present disclosure, a display device is provided, comprising the Micro LED display substrate provided by any of the above embodiments. In some embodiments, the display device may be a VR / AR display device, which can improve the resolution of the VR / AR display device and achieve full-color display. The display device may also be other display devices such as mobile phones, tablets, laptops, monitors, etc., without limitation herein. The display device provided by the present disclosure has the same technical effects as the Micro LED display substrate provided by any of the above embodiments, and will not be described in detail here.

[0134] FIG11 is a flow chart of a method for manufacturing a Micr LED display substrate provided in an embodiment of the present disclosure.

[0135] A third aspect of the present disclosure provides a method for manufacturing a Micro LED display substrate. As shown in FIG11 , the method for manufacturing a Micro LED display substrate provided by the present disclosure includes the following steps:

[0136] S111: forming multiple Micro LED structures on the driving backplane;

[0137] S112: Forming a plurality of color conversion structures on a side of the Micro LED structure facing away from the driving backplane.

[0138] In the method for manufacturing a Micro LED display substrate provided by the embodiments of the present disclosure, multiple Micro LED structures are first formed on a driving backplane, and then multiple color conversion structures are formed on the side of the Micro LED structure facing away from the driving backplane. The multiple Micro LED structures are used to emit light of the same color. As shown in FIG1 , one color conversion structure 300 corresponds to one Micro LED structure 200, and each color conversion structure 300 is located on the side of the corresponding Micro LED structure facing away from the driving backplane. The color conversion structure 300 converts the light emitted by the corresponding Micro LED structure 200 into light of a set color. Each color conversion structure 300 can emit light of a different color, thereby realizing the display of a full-color image.

[0139] In some embodiments, after forming multiple color conversion structures on the side of the Micro LED structure 200 facing away from the driver backplane 100, multiple spaced microlenses 400 may be further formed on the side of the color conversion structure 300 facing away from the driver backplane 100. As shown in FIG5 , one microlens 400 corresponds to one Micro LED structure 200, and each microlens 400 is located on the side of the corresponding Micro LED structure 200 facing away from the driver backplane 100. The orthographic projection of each color conversion structure 300 on the driver backplane 100 is within the orthographic projection of the microlens 400 on the driver backplane 100, thereby ensuring that more light emitted from the color conversion structure 300 is incident on the microlens 400. The microlens 400 adjusts the light output angle, thereby improving light utilization.

[0140] In a specific implementation, before forming the multiple color conversion structures 300 on the side of the Micro LED structure 200 facing away from the driver backplane 100, as shown in FIG5 , a first insulating layer 500 may also be deposited on the side of the multiple Micro LED structures 200 facing away from the driver backplane 100. The Micro LED structure 200 includes a bottom surface S1 and a top surface S2 disposed opposite each other, and a side surface S3 located between the bottom surface S1 and the top surface S2 and connected to the bottom surface S1 and the top surface S2, respectively. The first insulating layer 500 includes a first portion 510 covering the top surface S2 of the Micro LED structure 200, and a second portion 520 connected to the first portion 510 and covering the side surface S3 of the Micro LED structure 200. The first insulating layer 500 can provide insulation and protection for the Micro LED structure 200, facilitating the fabrication of the color conversion structures 300.

[0141] In some embodiments, as shown in FIG6 , when forming multiple color conversion structures 300 on the side of the Micro LED structure 200 facing away from the driver backplane 100, the orthographic projections of the color conversion structures 300 on the driver backplane 100 can be positioned within the orthographic projections of the first portion 510 of the first insulating layer 500 on the driver backplane 100. After forming the multiple color conversion structures 300 and before forming the microlenses 400, a light blocking layer 700 can be formed on the side of the first insulating layer 500 facing away from the driver backplane 100. The light blocking layer 700 fills the gaps between two adjacent Micro LED structures 200 and between two adjacent color conversion structures 300. The surface of the light blocking layer 700 facing away from the driver backplane 100 is connected to the surface of the adjacent color conversion structure 300 facing away from the driver backplane 100 to form a continuous surface. Then, a microlens 400 is formed on the side of the color conversion structure 300 and the light blocking layer 700 facing away from the driving backplane 100 , so that the microlens 400 covers the color conversion structure 300 and a portion of the light blocking layer 700 .

[0142] In some embodiments, as shown in FIG7 , when multiple color conversion structures 300 are formed on the side of the Micro LED structure 200 facing away from the driving backplane 100, the color conversion structures 300 can completely cover the first portion 510 of the first insulating layer 500 and at least partially cover the second portion 520 of the first insulating layer 500. After the color conversion structures 300 are formed, multiple spaced microlenses 400 are formed on the side of the color conversion structure 300 facing away from the driving backplane 100. The microlenses 400 cover the surface of the color conversion structure 300 and at least partially cover the surface of the first insulating layer 500 not covered by the color conversion structures 300, thereby enclosing the color conversion structures 300 within the microlenses 400. After the microlenses 400 are formed, a light blocking layer 700 is formed in the gaps between adjacent microlenses 400. The height of the light blocking layer 700, along a direction perpendicular to the driving backplane 100, is greater than or equal to the height of the color conversion structure 300.

[0143] In some embodiments, as shown in Figures 8 and 9 , the Micro LED structure 200 includes a bottom surface S1 and a top surface S2 disposed opposite each other, and a side surface S3 located between and connected to the bottom surface S1 and the top surface S2, respectively. In a specific implementation, before forming the plurality of color conversion structures 300 on the side of the Micro LED structure 200 facing away from the driver backplane 100, a plurality of spaced microlenses 400 may be formed on the side of the Micro LED structure 200 facing away from the driver backplane 100. Each microlens 400 corresponds to one Micro LED structure 200, and each microlens 400 is located on the side of the corresponding Micro LED structure 200 facing away from the driver backplane 100. The orthographic projections of the color conversion structures 300 and the Micro LED structure 200 on the driver backplane 100 are both located within the orthographic projections of the microlenses 400 on the driver backplane 100. The micro lens 400 covers the top surface S2 and at least a portion of the side surface S3 of the Micro LED structure, so as to at least partially enclose the Micro LED structure 200 within the micro lens 400 , thereby improving light utilization efficiency.

[0144] During specific implementation, the specific manufacturing method of the Micro LED display substrate provided by the embodiment of the present disclosure can refer to the specific structure of the aforementioned Micro LED display substrate, which will not be described in detail here.

[0145] Although the preferred embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present disclosure.

[0146] Obviously, those skilled in the art may make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include these modifications and variations.

Claims

1. A Micro LED display substrate, wherein: include: Driver backplane; A plurality of Micro LED structures are disposed on the driving backplane at intervals and are electrically connected to the driving backplane; Each of the Micro LED structures is used to emit light of the same color; Multiple color conversion structures, one color conversion structure corresponds to one Micro LED structure, each color conversion structure is located on a side of the corresponding Micro LED structure away from the driving backplane, and is used to convert the light emitted by the corresponding Micro LED structure into light of a set color.

2. The Micro LED display substrate according to claim 1, wherein: Also includes: A plurality of micro lenses arranged at intervals; One of the microlenses corresponds to one of the Micro LED structures, and each of the microlenses is located on a side of the corresponding Micro LED structure away from the driving backplane.

3. The Micro LED display substrate according to claim 2, wherein: The color conversion structure is located between the micro lens and the Micro LED structure; the orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the micro lens on the driving backplane; The Micro LED display substrate further includes: A first insulating layer, located between the Micro LED structure and the color conversion structure, and covering each of the Micro LED structures; The Micro LED structure includes a bottom surface and a top surface that are relatively arranged, and a side surface located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively; the first insulating layer includes a first portion covering the top surface of the Micro LED structure, and a second portion connected to the first portion and covering the side surface of the Micro LED structure.

4. The Micro LED display substrate according to claim 3, wherein: The orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the first portion of the first insulating layer on the driving backplane; The Micro LED display substrate further includes: A light blocking layer is located on a side of the first insulating layer away from the driving backplane and fills a gap between two adjacent Micro LED structures and a gap between two adjacent color conversion structures; a surface of the light blocking layer away from the driving backplane is connected to a surface of an adjacent color conversion structure away from the driving backplane to form a continuous surface; The micro lens is located on a side of the color conversion structure and the light blocking layer facing away from the driving backplane, and partially overlaps with the light blocking layer.

5. The Micro LED display substrate according to claim 3, wherein: The color conversion structure completely covers the first portion of the first insulating layer and at least partially covers the second portion of the first insulating layer; The microlens covers the surface of the color conversion structure and covers at least a portion of the surface of the first insulating layer not covered by the color conversion structure, so that the color conversion structure is wrapped within the microlens; The Micro LED display substrate further includes: A light blocking layer is filled in the gap between two adjacent micro lenses; Along a direction perpendicular to the driving backplane, a height of the light blocking layer is greater than or equal to a height of the color conversion structure.

6. The Micro LED display substrate according to claim 2, wherein: The color conversion structure is located on a side of the micro lens away from the Micro LED structure; The Micro LED structure includes a bottom surface and a top surface that are arranged opposite to each other, and side surfaces that are located between the bottom surface and the top surface and are respectively connected to the bottom surface and the top surface; the microlens covers the top surface and at least part of the side surface of the Micro LED structure to at least partially wrap the Micro LED structure within the microlens.

7. The Micro LED display substrate according to any one of claims 2 to 6, wherein: The surface of the microlens facing away from the driving back plate is a flat surface or a curved surface.

8. The Micro LED display substrate according to any one of claims 2 to 6, wherein: Also includes: A second insulating layer is located on a side of the microlens away from the driving backplane; The second insulating layer is in direct contact with the microlenses and covers the microlenses and the gaps between the microlenses, so as to form a flat surface on a side of the microlenses away from the driving backplane.

9. The Micro LED display substrate according to any one of claims 1 to 6, wherein: The Micro LED structure includes: A first electrode, located at a side close to the driving back plate and electrically connected to the driving back plate; A first doping layer, located on a side of the first electrode away from the driving back plate; a multi-quantum well layer, located on a side of the first doped layer away from the first electrode; A second doped layer is located on a side of the multi-quantum well layer away from the first doped layer; a third insulating layer, located on a side of the second doped layer away from the driving backplane; the third insulating layer comprises an opening exposing the second doped layer; the third insulating layer covers surfaces of the multi-quantum well layer, the first doped layer and the first electrode, so as to wrap the multi-quantum well layer, the first doped layer and the first electrode within the third insulating layer; a second electrode, located on a side of the third insulating layer away from the driving backplane; the second electrode covers a surface of the third insulating layer and is electrically connected to the second doping layer through the opening; the second electrode is also electrically connected to the driving backplane; The Micro LED display backplane also includes: A conductive filling layer is located in a gap between two adjacent Micro LED structures; the conductive filling layer is directly formed on a surface of the second electrode and is electrically connected to the second electrode.

10. The Micro LED display substrate according to claim 9, wherein: Along a direction perpendicular to the driving backplane, a height of the conductive filling layer is less than a height of the Micro LED structure.

11. The Micro LED display substrate according to any one of claims 1 to 6, wherein: The color conversion structure includes a color conversion layer; the color conversion layer is used to convert at least part of the light emitted by the Micro LED structure into light of a set color.

12. The Micro LED display substrate according to claim 11, wherein: Each of the color conversion structures further includes: a filter layer located on a side of the color conversion layer away from the Micro LED structure; the filter layer is used to filter out light having a color different from the color of the light emitted after the color conversion of the color conversion layer.

13. A display device, wherein: It comprises the Micro LED display substrate as claimed in any one of claims 1 to 12.

14. A method for manufacturing a Micro LED display substrate, wherein: include: Forming a plurality of Micro LED structures on a driving backplane; A plurality of color conversion structures are formed on a side of the Micro LED structure away from the driving backplane; wherein one color conversion structure corresponds to one Micro LED structure, and each color conversion structure is located on a side of the corresponding Micro LED structure away from the driving backplane.

15. The method of claim 14, wherein: Also includes: A plurality of spaced micro lenses are formed on a side of the color conversion structure away from the driving backplane; wherein one micro lens corresponds to one Micro LED structure, and each micro lens is located on a side of the corresponding Micro LED structure away from the driving backplane; Before forming a plurality of color conversion structures on a side of the Micro LED structure away from the driving backplane, the method further includes: A first insulating layer is deposited on a side of the multiple Micro LED structures away from the driving backplane; wherein the Micro LED structure includes a bottom surface and a top surface that are relatively arranged, and a side surface located between the bottom surface and the top surface and connected to the bottom surface and the top surface respectively; the first insulating layer includes a first portion covering the top surface of the Micro LED structure, and a second portion connected to the first portion and covering the side surface of the Micro LED structure.

16. The method of claim 15, wherein: The forming of a plurality of color conversion structures on a side of the Micro LED structure away from the driving backplane specifically includes: The orthographic projection of the color conversion structure on the driving backplane is located within the orthographic projection of the first portion of the first insulating layer on the driving backplane; Before manufacturing a plurality of spaced micro lenses on a side of the color conversion structure away from the driving backplane, the method further comprises: A light blocking layer is formed on the side of the first insulating layer away from the driving backplane; wherein the light blocking layer is filled in the gap between two adjacent Micro LED structures and in the gap between two adjacent color conversion structures; the surface of the light blocking layer away from the driving backplane is connected to the surface of the adjacent color conversion structure away from the driving backplane to form a into a continuous surface; The step of manufacturing a plurality of spaced micro lenses on a side of the color conversion structure away from the driving backplane specifically includes: The microlens is formed on a side of the color conversion structure and the light blocking layer facing away from the driving backplane.

17. The method of claim 15, wherein: The forming of a plurality of color conversion structures on a side of the Micro LED structure away from the driving backplane specifically includes: The color conversion structure completely covers the first portion of the first insulating layer and at least partially covers the second portion of the first insulating layer; The step of manufacturing a plurality of spaced micro lenses on a side of the color conversion structure away from the driving backplane specifically includes: The microlens covers the surface of the color conversion structure and covers at least a portion of the surface of the first insulating layer not covered by the color conversion structure, so that the color conversion structure is wrapped within the microlens; The method further comprises: A light blocking layer is formed in the gap between two adjacent micro lenses; wherein, along a direction perpendicular to the driving backplane, the height of the light blocking layer is greater than or equal to the height of the color conversion structure.

18. The method of claim 14, wherein: The Micro LED structure includes a bottom surface and a top surface that are oppositely arranged, and a side surface that is located between the bottom surface and the top surface and is connected to the bottom surface and the top surface respectively; Before forming a plurality of color conversion structures on a side of the Micro LED structure away from the driving backplane, the method further includes: A plurality of spaced micro lenses are formed on a side of the Micro LED structure away from the driving backplane; wherein one micro lens corresponds to one Micro LED structure, and each micro lens is located on a side of the corresponding Micro LED structure away from the driving backplane; the orthographic projection of the color conversion structure on the driving backplane and the orthographic projection of the Micro LED structure on the driving backplane The orthographic projections are all located within the orthographic projections of the microlenses on the driving backplane; the microlenses cover the top surface and at least a portion of the side surfaces of the Micro LED structure, so as to at least partially wrap the Micro LED structure within the microlenses; The forming of a plurality of color conversion structures on a side of the Micro LED structure away from the driving backplane specifically includes: The color conversion structure is formed on a side of the microlens facing away from the driving backplane.

Images