Miniature light emitting diode display

Abstract

The utility model relates to the technical field of semiconductor devices, and discloses a micro light-emitting diode display. The micro light emitting diode display includes a substrate, a first LED unit layer, a second LED unit layer, and a color conversion layer. The first LED unit layer is fused and bonded above the substrate and comprises a plurality of first LED units, and the first LED units emit first color light. And the second LED unit layer is fused and bonded above the first LED unit layer and comprises a plurality of second LED units, and the second LED units emit second color light. The color conversion layer comprises a plurality of color conversion units, and the color conversion units are arranged above the corresponding second LED units and convert the corresponding second color light into third color light. Or the color conversion units penetrate through the second LED unit layer and are arranged above the corresponding first LED units, and the corresponding first color light is converted into the third color light. Through combination of fusion bonding and color conversion, the processing difficulty is reduced, the size is reduced, heat concentration is reduced, and the heat dissipation effect is improved.

Description

Miniature LED Display Technical Field

[0001] This application belongs to the field of semiconductor device technology, and specifically relates to a miniature light-emitting diode display. Background Technology

[0002] In related technologies, miniature light-emitting diode (LED) displays include at least three layers of LED units. By emitting light through different layers of LED units, red, green, and blue light are combined to achieve full-color display. This results in the high manufacturing difficulty and relatively large size of miniature LED displays, as well as heat concentration, which affects heat dissipation and reduces display quality. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the related art.

[0004] Therefore, this application provides a miniature light-emitting diode display.

[0005] This application provides a micro light-emitting diode display, comprising: a substrate; a first LED unit layer, fused and bonded to the top of the substrate, comprising a plurality of first LED units arranged at intervals, the first LED units emitting a first color light; a second LED unit layer, fused and bonded to the top of the first LED unit layer, comprising a plurality of second LED units arranged at intervals, the second LED units emitting a second color light; a color conversion layer, comprising a plurality of color conversion units arranged at intervals, the color conversion units being disposed above corresponding second LED units for converting corresponding second color light into third color light; or, the color conversion units penetrating the second LED unit layer and disposed above corresponding first LED units for converting corresponding first color light into third color light, the first color light, the second color light, and the third color light being different; at least one first LED unit, at least one adjacent second LED unit, and at least one adjacent color conversion unit constitute a full-color pixel.

[0006] In one possible implementation, the first LED unit layer further includes a first planarization layer, which fills the spaces between adjacent first LED units and is fused to the substrate to create a gap between the first LED units and the substrate; the micro LED display further includes a first planarization layer disposed above the first LED unit layer; the second LED unit layer further includes a second planarization layer, which fills the spaces between adjacent second LED units and is fused to the first planarization layer to create a gap between the second LED units and the first planarization layer.

[0007] In one possible implementation, the first LED unit layer further includes a first planarization layer and a first bonding layer, wherein the first planarization layer fills the spaces between adjacent first LED units and is fused to the substrate via the first bonding layer; the micro LED display further includes a first planarization layer disposed above the first LED unit layer; the second LED unit layer further includes a second planarization layer and a second bonding layer, wherein the second planarization layer fills the spaces between adjacent second LED units and is fused to the first planarization layer via the second bonding layer.

[0008] In one possible implementation, the first LED unit and the second LED unit respectively include a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The micro LED display further includes: a first electrode layer disposed above the first LED unit and electrically connected to the second doped semiconductor layer of the first LED unit; a second electrode layer disposed above the second LED unit and connected to the second doped semiconductor layer of the second LED unit; and a common conductive post for electrically connecting to an adjacent first electrode layer and / or an adjacent second electrode layer. The color conversion unit is disposed on the upper surface of the first electrode layer or the second electrode layer.

[0009] In one possible implementation, the substrate includes a plurality of first contacts, and the micro LED display further includes: a first conductive structure electrically connected to the first doped semiconductor layer of the first LED unit; a first conductive post penetrating the first LED unit layer for electrically connecting the first conductive structure and the corresponding first contact; a second conductive structure electrically connected to the first doped semiconductor layer of the second LED unit; and a second conductive post penetrating the first LED unit layer and the second LED unit layer for electrically connecting the second conductive structure and the corresponding first contact.

[0010] In one possible implementation, the first conductive structure includes a first conductive layer disposed below the first LED unit; the second conductive structure includes a second conductive layer disposed below the second LED unit.

[0011] In one possible implementation, the first conductive structure includes a first conductive reflective cup surrounding the side and bottom of the first LED unit; the second conductive structure includes a second conductive reflective cup surrounding the side and bottom of the second LED unit.

[0012] In one possible implementation, the first LED unit layer further includes a first passivation layer, which is at least disposed between the first LED unit and the first conductive reflective cup; the second LED unit layer further includes a second passivation layer, which is at least disposed between the second LED unit and the second conductive reflective cup.

[0013] In one possible implementation, the micro LED display further includes: a second planarization layer disposed above the second LED unit layer; a filling hole penetrating at least through the second planarization layer and the second LED unit layer, and exposing the upper surface of the corresponding first electrode layer; and a reflective metal layer disposed on the inner wall of the filling hole and connected to the corresponding first electrode layer; wherein the color conversion unit is formed within the filling hole and covers the reflective metal layer.

[0014] In one possible implementation, the micro LED display further includes: a second planarization layer disposed above the second LED unit layer; a color conversion adhesive layer disposed above the second planarization layer; a filling hole penetrating the color conversion adhesive layer and the second planarization layer, and exposing the upper surface of the corresponding second electrode layer; and a reflective metal layer disposed on the inner wall of the filling hole and connected to the corresponding second electrode layer; wherein the color conversion unit is formed in the filling hole and covers the reflective metal layer.

[0015] In one possible implementation, the micro LED display further includes: a filling hole that penetrates at least through the second LED unit layer and exposes the upper surface of the corresponding first electrode layer; a reflective metal layer disposed on the inner wall of the filling hole and connected to the corresponding first electrode layer; wherein the color conversion unit is formed in the filling hole and covers the reflective metal layer.

[0016] In one possible implementation, the micro LED display further includes: a color conversion adhesive layer disposed above the second LED unit layer; a filling hole penetrating the color conversion adhesive layer and exposing the upper surface of the corresponding second electrode layer; and a reflective metal layer disposed on the inner wall of the filling hole and connected to the corresponding second electrode layer; wherein the color conversion unit is formed in the filling hole and covers the reflective metal layer.

[0017] The miniature light-emitting diode display provided in this application can achieve at least the following technical effects:

[0018] The first LED unit layer is fused and bonded to the substrate, and the second LED unit layer is fused and bonded to the first LED unit layer, reducing processing difficulty and improving device yield. A color conversion unit is located above the corresponding second LED unit, or the color conversion unit penetrates the second LED unit layer and is located above the corresponding first LED unit. This combination of fusion bonding and color conversion reduces processing difficulty, decreases the overall size of the micro-LED display, reduces heat concentration, improves heat dissipation, and thus improves display performance. Full-color display is achieved by using different first, second, and third colors of light, along with at least one first LED unit, at least one adjacent second LED unit, and at least one adjacent color conversion unit to form a full-color pixel.

[0019] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0020] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein:

[0021] Figure 1 is a schematic diagram of the structure of a miniature light-emitting diode display provided in an embodiment of the present disclosure;

[0022] Figure 2 is a schematic diagram of the structure of a miniature light-emitting diode display provided in another embodiment of this disclosure;

[0023] Figure 3 is a schematic diagram of the structure of a miniature light-emitting diode display provided in another embodiment of this disclosure;

[0024] Figure 4 is a schematic diagram of the structure of a micro light-emitting diode display provided in another embodiment of the present disclosure.

[0025] The reference numerals in the attached figures are as follows:

[0026] 1: Miniature LED display;

[0027] 10: Substrate; 11: First contact point;

[0028] 20: First LED unit layer; 21: First LED unit; 22: First filler layer; 23: First bonding layer; 24: First passivation layer;

[0029] 30: Second LED unit layer; 31: Second LED unit; 32: Second leveling layer; 33: Second bonding layer; 34: Second passivation layer;

[0030] 40: Color conversion layer; 41: Color conversion unit;

[0031] 50: First planarization layer; 51: Second planarization layer;

[0032] 60: First electrode layer; 61: Second electrode layer;

[0033] 70: Common conductive post; 71: First conductive post; 72: Second conductive post;

[0034] 80: First conductive layer; 81: Second conductive layer; 82: First conductive reflective cup; 83: Second conductive reflective cup;

[0035] 90: Filler hole; 91: Reflective metal layer; 92: Color conversion adhesive layer. Detailed Implementation

[0036] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0037] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0038] In this disclosure, the terms "upper," "lower," "inner," "middle," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for better description of the embodiments of this disclosure and their implementations, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this disclosure according to the specific circumstances.

[0039] Furthermore, the terms "set up," "connect," and "fix" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0040] Unless otherwise stated, the term "multiple" means two or more.

[0041] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in the present disclosure can be combined with each other.

[0043] As used in embodiments of this disclosure, the term "layer" refers to a portion of material comprising a region having a certain thickness. A layer may extend over the entire lower or upper structure, or may have a extent smaller than that of the lower or upper structure. A layer may extend horizontally, vertically, and / or along a tapered surface.

[0044] The term "micro" as used in the embodiments of this disclosure refers to the descriptive size of certain devices or structures according to embodiments of this application. The term "micro" as used herein is intended to indicate a scale from 0.1 μm to 100 μm. However, it should be understood that embodiments of this application are not necessarily limited thereto, and certain aspects of the embodiments can be applied to larger and possibly smaller size scales.

[0045] As used in embodiments of this disclosure, the term "substrate" refers to the material on which subsequent material layers are added. The substrate itself may be patterned. The material added on top of the substrate may be patterned or may remain unpatterned. Furthermore, the substrate may comprise a wide variety of semiconductor materials, such as silicon, silicon carbide, gallium nitride, germanium, gallium arsenide, and indium phosphide. Alternatively, the substrate may be made of a non-conductive material, such as glass, plastic, or sapphire wafer. Further alternatively, the substrate may have semiconductor devices or circuits formed therein.

[0046] Referring to Figures 1 to 4, this application provides a micro LED display 1, including a substrate 10, a first LED unit layer 20, a second LED unit layer 30, and a color conversion layer 40. The first LED unit layer 20 is fused and bonded to the substrate 10, and includes a plurality of spaced-apart first LED units 21 emitting a first color light. The second LED unit layer 30 is fused and bonded to the first LED unit layer 20, and includes a plurality of spaced-apart second LED units 31 emitting a second color light. The color conversion layer 40 includes a plurality of spaced-apart color conversion units 41, each disposed above a corresponding second LED unit 31, for converting the corresponding second color light into a third color light. Alternatively, the color conversion unit 41 penetrates the second LED unit layer 30 and is disposed above a corresponding first LED unit 21, for converting the corresponding first color light into a third color light. The first, second, and third colors are different. At least one first LED unit 21, at least one adjacent second LED unit 31, and at least one adjacent color conversion unit 41 constitute a full-color pixel.

[0047] By fusion bonding the first LED unit layer 20 to the substrate 10 and fusion bonding the second LED unit layer 30 to the first LED unit layer 20, the processing difficulty is reduced and the device yield is improved.

[0048] A color conversion unit 41 is disposed above the corresponding second LED unit 31 to convert the second color light emitted by the corresponding second LED unit 31 into a third color light, thereby reducing processing difficulty. For example, the second color light is green light and the third color light is red light; the color conversion unit 41 is used to convert the green light emitted by the second LED unit 31 into red light. In the description of the disclosed embodiments, "corresponding" refers to the relationship between two structures that need to be interconnected or whose positions need to be corresponding, which will not be elaborated further below.

[0049] A color conversion unit 41 penetrates the second LED unit layer 30 and is positioned above the corresponding first LED unit 21. It converts the first color light emitted by the first LED unit 21 into a third color light, thereby reducing processing difficulty and achieving thinning in the thickness direction (vertical direction), thus reducing the overall size of the micro LED display 1. For example, the first color light is blue light, and the third color light is red light; the color conversion unit 41 is used to convert the blue light emitted by the first LED unit 21 into red light.

[0050] By combining two fusion bonding processes and one color conversion, the processing difficulty is reduced, the size of the micro LED display 1 is decreased, heat concentration is reduced, heat dissipation is improved, and thus the display effect is enhanced.

[0051] The first LED unit 21 emits a first color light, the second LED unit 31 emits a second color light, and the color conversion unit 41 converts the corresponding first color light or second color light into a third color light. The first color light, the second color light, and the third color light are different, so that at least one first LED unit 21, at least one adjacent second LED unit 31, and at least one adjacent color conversion unit 41 constitute a full-color pixel, thereby realizing full-color display.

[0052] The substrate 10 may be provided with a circuit layer including complementary metal oxide semiconductor (CMOS) devices or thin film field effect transistor (TFT) devices, which can constitute a driving circuit.

[0053] In this embodiment, the projections of the first LED unit 21 and the second LED unit 31 in the vertical direction may or may not overlap, as long as full-color display can be achieved. In the description of the disclosed embodiments, the vertical direction refers to the direction perpendicular to the upper surface of the substrate 10, which will not be repeated below.

[0054] Referring to Figures 1 to 4, in one possible implementation, the projection of the color conversion unit 41 in the vertical direction covers the corresponding first LED unit 21 or second LED unit 31 to improve the color conversion effect.

[0055] In one possible implementation, the material of the color conversion unit 41 includes quantum dot photoresist.

[0056] Referring to Figures 1 and 2, in some embodiments, the first LED unit layer 20 further includes a first planarization layer 22, which fills the spaces between adjacent first LED units 21 and is fused-bonded to the substrate 10 to create a gap between the first LED units 21 and the substrate 10. The micro LED display 1 further includes a first planarization layer 50, which is disposed above the first LED unit layer 20. The second LED unit layer 30 further includes a second planarization layer 32, which fills the spaces between adjacent second LED units 31 and is fused-bonded to the first planarization layer 50 to create a gap between the second LED units 31 and the first planarization layer 50.

[0057] The first filler layer 22 is filled between adjacent first LED units 21 and fused to the substrate 10, so that the first LED unit layer 20 is fused to the substrate 10. This simplifies the processing and reduces the difficulty of fabrication. The spacing between the first LED units 21 and the substrate 10 improves the reliability of the fused bonding, thereby enhancing device performance. The material of the first filler layer 22 is not limited; for example, it can be silicon dioxide.

[0058] The first planarization layer 50 protects the first LED unit 21 and provides a basis for fused bonding processing, improving the reliability of fused bonding. The material of the first planarization layer 50 is not limited; for example, it can be silicon dioxide.

[0059] The second leveling layer 32 fills the spaces between adjacent second LED units 31 and is fused-bonded to the first planarization layer 50, thus fusion-bonding the second LED unit layer 30 onto the first LED unit layer 20. This simplifies the manufacturing process and reduces processing difficulty. The spacing between the second LED units 31 and the first planarization layer 50 improves the reliability of the fusion bonding, thereby enhancing device performance. The material of the second leveling layer 32 is not limited; for example, it can be silicon dioxide.

[0060] Referring to Figures 3 and 4, in some embodiments, the first LED unit layer 20 further includes a first planarization layer 22 and a first bonding layer 23. The first planarization layer 22 fills the spaces between adjacent first LED units 21 and is fused to the substrate 10 via the first bonding layer 23. The micro LED display 1 further includes a first planarization layer 50 disposed above the first LED unit layer 20. The second LED unit layer 30 further includes a second planarization layer 32 and a second bonding layer 33. The second planarization layer 32 fills the spaces between adjacent second LED units 31 and is fused to the first planarization layer 50 via the second bonding layer 33.

[0061] Specifically, the first bonding layer 23 is located between the substrate 10 and the first planarization layer 22. In actual processing, the first bonding layer 23 can be formed on the first planarization layer 22 first, and then fused and bonded to the substrate 10 to fused and bond the first LED unit layer 20 onto the substrate 10. This simplifies the processing, reduces processing difficulty, and improves the reliability of fused bonding. The material of the first bonding layer 23 is not limited; for example, it can be silicon dioxide. The technical effects of the first planarization layer 50 are described in the foregoing embodiments of this application and will not be repeated here.

[0062] The second bonding layer 33 is located between the first planarization layer 50 and the second leveling layer 32. In actual processing, the second bonding layer 33 can be formed first on the second leveling layer 32 and then fused and bonded to the first planarization layer 50, thereby fused and bonded the second LED unit layer 30 onto the first LED unit layer 20. This simplifies the processing, reduces processing difficulty, and improves the reliability of the fused bonding. The material of the second bonding layer 33 is not limited; for example, it can be silicon dioxide.

[0063] Referring to Figures 1 to 4, in some embodiments, the first LED unit 21 and the second LED unit 31 respectively include a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The micro LED display 1 also includes a first electrode layer 60, a second electrode layer 61, and a common conductive post 70. The first electrode layer 60 is disposed above the first LED unit 21 and is electrically connected to the second doped semiconductor layer of the first LED unit 21. The second electrode layer 61 is disposed above the second LED unit 31 and is connected to the second doped semiconductor layer of the second LED unit 31. The common conductive post 70 is used for electrical connection with adjacent first electrode layers 60 and / or adjacent second electrode layers 61. The color conversion unit 41 is disposed on the upper surface of the first electrode layer 60 or the second electrode layer 61.

[0064] The first LED unit 21 includes a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The first electrode layer 60 is electrically connected to the second doped semiconductor layer of the first LED unit 21, thereby realizing the electrical connection between the first electrode layer 60 and the first LED unit 21. The material of the first electrode layer 60 is not limited; for example, it can be indium tin oxide (ITO).

[0065] The second LED unit 31 includes a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The second electrode layer 61 is electrically connected to the second doped semiconductor layer of the second LED unit 31. The material of the second electrode layer 61 is not limited; for example, it can be indium tin oxide (ITO).

[0066] The first doped semiconductor layer can be a p-type semiconductor layer, specifically p-type gallium nitride (GaN) or p-type aluminum indium gallium nitride (AlInGaN). The second doped semiconductor layer can be an n-type semiconductor layer, specifically n-type gallium nitride (GaN) or n-type aluminum indium gallium nitride (AlInGaN).

[0067] The common conductive post 70 is electrically connected to the adjacent first electrode layer 60 and / or the adjacent second electrode layer 61, so that the first electrode layer 60 and / or the second electrode layer 61 can be electrically connected to the substrate 10 through the common conductive post 70. For example, by connecting the common conductive post 70 to the adjacent first electrode layer 60, the first electrode layer 60 can be connected to the cathode contact of the substrate 10 through the common conductive post 70. Similarly, by connecting the common conductive post 70 to the adjacent second electrode layer 61, the second electrode layer 61 can be connected to the cathode contact of the substrate 10 through the common conductive post 70. Furthermore, by connecting the common conductive post 70 to both the adjacent first electrode layer 60 and the adjacent second electrode layer 61, the first electrode layer 60 and the second electrode layer 61 can be jointly connected to the cathode contact of the substrate 10 through the common conductive post 70. The material of the common conductive post 70 is not limited; for example, it can be copper or tungsten.

[0068] When the color conversion unit 41 is positioned above the corresponding first LED unit 21, the color conversion unit 41 is located on the upper surface of the first electrode layer 60, further reducing the size of the micro LED display 1 and improving the overall display effect. When the color conversion unit 41 is positioned above the corresponding second LED unit 31, the color conversion unit 41 is located on the upper surface of the second electrode layer 61, further reducing the size of the micro LED display 1 and improving the overall display effect.

[0069] Referring to Figures 1 to 4, in some embodiments, the substrate 10 includes a plurality of first contacts 11. The micro LED display 1 further includes a first conductive structure, a first conductive post 71, a second conductive structure, and a second conductive post 72. The first conductive structure is electrically connected to the first doped semiconductor layer of the first LED unit 21. The first conductive post 71 penetrates the first LED unit layer 20 and is used to electrically connect the first conductive structure to the corresponding first contact 11. The second conductive structure is electrically connected to the first doped semiconductor layer of the second LED unit 31. The second conductive post 72 penetrates the first LED unit layer 20 and the second LED unit layer 30 and is used to electrically connect the second conductive structure to the corresponding first contact 11.

[0070] The substrate 10 includes a plurality of first contacts 11, which may be anode contacts. The substrate 10 also includes at least one cathode contact (not shown in the figure) to enable each first LED unit 21 and each second LED unit 31 to be driven individually.

[0071] The first conductive structure is electrically connected to the first doped semiconductor layer of the first LED unit 21. The first conductive post 71 is used to electrically connect the first conductive structure and the corresponding first contact 11, so that each first LED unit 21 can be driven individually, and the active layer of the first LED unit 21 can emit light. The material of the first conductive post 71 is not limited, for example, it can be copper or tungsten.

[0072] The second conductive structure is electrically connected to the first doped semiconductor layer of the second LED unit 31. The second conductive post 72 is used to electrically connect the second conductive structure to the corresponding first contact 11, so that each second LED unit 31 can be driven individually, enabling the active layer of the second LED unit 31 to emit light. The material of the second conductive post 72 is not limited; for example, it can be copper or tungsten.

[0073] For example, referring to Figures 1 to 4, the second conductive post 72 may include a first post segment penetrating the first LED unit layer 20 and a second post segment penetrating the second LED unit layer 30. In actual processing, the first post segment can be formed in the same step as the first conductive post 71, and then the second post segment can be connected to the first post segment when forming the second post segment to obtain the second conductive post 72.

[0074] Referring to Figures 3 and 4, in some embodiments, the first conductive structure includes a first conductive layer 80, which is disposed below the first LED unit 21. The second conductive structure includes a second conductive layer 81, which is disposed below the second LED unit 31.

[0075] By placing the first conductive layer 80 below the first LED unit 21, electrical connection can be achieved between the first conductive layer 80 and the first doped semiconductor layer of the first LED unit 21, and electrical connection with the substrate 10 can be facilitated. The material of the first conductive layer 80 is not limited; for example, it can be indium tin oxide (ITO).

[0076] By disposing the second conductive layer 81 below the second LED unit 31, electrical connection can be achieved between the second conductive layer 81 and the first doped semiconductor layer of the second LED unit 31, and electrical connection with the substrate 10 can be facilitated. The material of the second conductive layer 81 is not limited, for example, it can be indium tin oxide (ITO).

[0077] In one possible implementation, the projections of the first LED unit 21 and the first contact 11 in the vertical direction do not overlap, so that the first LED unit 21 and the corresponding first contact 11 are not connected in the same vertical direction, reducing the difficulty of alignment during connection processing and increasing the operating space, thus avoiding or reducing damage to the first LED unit 21 during connection processing.

[0078] As shown in Figures 3 and 4, in one possible implementation, the first conductive layer 80 extends out of the first LED unit 21 so that the first LED unit 21 can be electrically connected to the corresponding first contact 11, reducing the processing difficulty.

[0079] In one possible implementation, the projections of the second LED unit 31 and the first contact 11 in the vertical direction do not overlap, so that the second LED unit 31 and the corresponding first contact 11 are not connected in the same vertical direction, reducing the difficulty of alignment during connection processing and increasing the operating space, thus avoiding or reducing damage to the first LED unit 21 during connection processing.

[0080] As shown in Figures 3 and 4, in one possible implementation, the second conductive layer 81 extends out of the second LED unit 31 so that the second LED unit 31 can be electrically connected to the corresponding first contact 11, reducing the processing difficulty.

[0081] Referring to Figures 1 and 2, in some embodiments, the first conductive structure includes a first conductive reflective cup 82, which surrounds the sides and bottom of the first LED unit 21. The second conductive structure includes a second conductive reflective cup 83, which surrounds the sides and bottom of the second LED unit 31.

[0082] By surrounding the sides and bottom of the first LED unit 21 with the first conductive reflective cup 82, the light emitted by the first LED unit 21 can be reflected as much as possible, reducing the amount of light hitting adjacent pixels, improving light extraction efficiency, preventing or reducing optical crosstalk, and making the light spot more concentrated and the pixels more compact, thereby improving the resolution and display effect of the device. The material of the first conductive reflective cup 82 is not limited; for example, it can be a suitable metal or alloy.

[0083] By surrounding the sides and bottom of the second LED unit 31 with the second conductive reflective cup 83, the light emitted by the second LED unit 31 can be reflected as much as possible, reducing the amount of light hitting adjacent pixels, improving light extraction efficiency, preventing or reducing optical crosstalk, and making the light spot more concentrated and the pixels more compact, thereby improving the resolution and display effect of the device. The material of the second conductive reflective cup 83 is not limited; for example, it can be a suitable metal or alloy.

[0084] Referring to Figures 1 and 2, in one possible implementation, the first conductive reflective cup 82 is electrically connected to the first doped semiconductor layer of the first LED unit 21, and the first conductive reflective cup 82 extends toward the side of the first LED unit 21 so that the first LED unit 21 can be electrically connected to the corresponding first contact 11, reducing the processing difficulty.

[0085] Referring to Figures 1 and 2, in one possible implementation, the second conductive reflective cup 83 is electrically connected to the first doped semiconductor layer of the second LED unit 31, and the second conductive reflective cup 83 extends toward the side of the second LED unit 31 so that the second LED unit 31 can be electrically connected to the corresponding first contact 11, reducing the processing difficulty.

[0086] Referring to Figures 1 and 2, in some embodiments, the first LED unit layer 20 further includes a first passivation layer 24, which is at least disposed between the first LED unit 21 and the first conductive reflective cup 82. The second LED unit layer 30 further includes a second passivation layer 34, which is at least disposed between the second LED unit 31 and the second conductive reflective cup 83.

[0087] When the first conductive structure includes a first conductive reflective cup 82, the first LED unit layer 20 also includes a first passivation layer 24. The first passivation layer 24 is at least disposed between the first LED unit 21 and the first conductive reflective cup 82 to protect the first LED unit 21 and prevent or reduce leakage. The first passivation layer 24 can also extend to the upper surface of the first leveling layer 22, and make the upper surface of the first passivation layer 24 flush with the upper surface of the first LED unit 21. This allows the first passivation layer 24 to serve as a position reference during processing, reducing the difficulty of the processing technology, improving processing efficiency and accuracy, avoiding or reducing damage to the device caused by over-processing, and achieving protection of the first LED unit 21 during processing. The material of the first passivation layer 24 is not limited; for example, it can be silicon dioxide or aluminum oxide.

[0088] When the second conductive structure includes a second conductive reflective cup 83, the second LED unit layer 30 also includes a second passivation layer 34. The second passivation layer 34 is disposed at least between the second LED unit 31 and the second conductive reflective cup 83 to protect the second LED unit 31 and prevent or reduce leakage. The second passivation layer 34 can also extend to the upper surface of the second leveling layer 32, and make the upper surface of the second passivation layer 34 flush with the upper surface of the second LED unit 31. This allows the second passivation layer 34 to serve as a position reference during processing, reducing the difficulty of the processing technology, improving processing efficiency and accuracy, avoiding or reducing device damage caused by over-processing, and achieving protection of the second LED unit 31 during processing. The material of the second passivation layer 34 is not limited; for example, it can be silicon dioxide or aluminum oxide.

[0089] Referring to Figure 1, in some embodiments, the micro LED display 1 further includes a second planarization layer 51, a filling hole 90, and a reflective metal layer 91. The second planarization layer 51 is disposed above the second LED unit layer 30. The filling hole 90 penetrates at least through the second planarization layer 51 and the second LED unit layer 30, exposing the upper surface of the corresponding first electrode layer 60. The reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and connected to the corresponding first electrode layer 60. A color conversion unit 41 is formed within the filling hole 90 and covers the reflective metal layer 91.

[0090] The second planarization layer 51 is disposed above the second LED unit layer 30 to prepare for the formation of the color conversion layer 40. The material of the second planarization layer 51 is not limited; for example, it can be silicon dioxide.

[0091] The filling hole 90 penetrates at least through the second planarization layer 51 and the second LED unit layer 30. The filling hole 90 can also extend to the first planarization layer 50 to expose the upper surface of the corresponding first electrode layer 60, so that the color conversion unit 41 is disposed on the upper surface of the first electrode layer 60, thereby reducing the thickness.

[0092] The reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and connected to the corresponding first electrode layer 60, thereby reducing the resistance of the first electrode layer 60 and reducing power consumption.

[0093] A color conversion unit 41 is formed within the filling hole 90 and covered by a reflective metal layer 91, which improves light extraction efficiency, prevents or reduces optical crosstalk, and makes the light spot more concentrated and the pixels more compact, thereby improving the resolution and display effect of the device. The material of the reflective metal layer 91 is not limited; for example, it can be a suitable metal or alloy.

[0094] Referring to Figure 2, in some embodiments, the micro LED display 1 further includes a second planarization layer 51, a color conversion adhesive layer 92, and a filling hole 90. The second planarization layer 51 is disposed above the second LED unit layer 30. The color conversion adhesive layer 92 is disposed above the second planarization layer 51. The filling hole 90 penetrates the color conversion adhesive layer 92 and the second planarization layer 51, exposing the upper surface of the corresponding second electrode layer 61. A reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and connected to the corresponding second electrode layer 61. A color conversion unit 41 is formed within the filling hole 90 and covers the reflective metal layer 91.

[0095] The color conversion resist layer 92 is disposed above the second planarization layer 51 to prepare for the formation of the color conversion layer 40. The material of the color conversion resist layer 92 is not limited; for example, it can be quantum dot photoresist.

[0096] The reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and connected to the corresponding second electrode layer 61, thereby reducing the resistance of the second electrode layer 61 and reducing power consumption.

[0097] The technical effects of the second planarization layer 51, the filling hole 90, and the color conversion unit 41 covering the reflective metal layer 91 are described in the foregoing embodiments of this application and will not be repeated here.

[0098] Referring to Figure 3, in some embodiments, the micro LED display 1 further includes a filling hole 90 and a reflective metal layer 91. The filling hole 90 penetrates at least through the second LED unit layer 30 and exposes the upper surface of the corresponding first electrode layer 60. The reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and connected to the corresponding first electrode layer 60. A color conversion unit 41 is formed within the filling hole 90 and covers the reflective metal layer 91.

[0099] The filling hole 90 penetrates at least through the second LED unit layer 30 and extends to the first planarization layer 50 to expose the upper surface of the corresponding first electrode layer 60 so that the color conversion unit 41 is disposed on the upper surface of the first electrode layer 60, thereby reducing the thickness.

[0100] The technical effects of the reflective metal layer 91 and the color conversion unit 41 covering the reflective metal layer 91 are described in the foregoing embodiments of this application and will not be repeated here.

[0101] Referring to Figure 4, in some embodiments, the micro LED display 1 further includes a color conversion adhesive layer 92, a filling hole 90, and a reflective metal layer 91. The color conversion adhesive layer 92 is disposed above the second LED unit layer 30. The filling hole 90 penetrates the color conversion adhesive layer 92 and exposes the upper surface of the corresponding second electrode layer 61. The reflective metal layer 91 is disposed on the inner wall of the filling hole 90 and is connected to the corresponding second electrode layer 61. A color conversion unit 41 is formed within the filling hole 90 and covers the reflective metal layer 91.

[0102] The color conversion adhesive layer 92 is disposed above the second LED unit layer 30 to prepare for the formation of the color conversion layer 40.

[0103] The technical effects of filling the hole 90, the reflective metal layer 91, and the color conversion unit 41 covering the reflective metal layer 91 are described in the foregoing embodiments of this application and will not be repeated here.

[0104] This disclosure also provides a display device. The display device includes a miniature light-emitting diode display 1 as described in any of the preceding embodiments. Therefore, the display device has the beneficial effects of the miniature light-emitting diode display 1 as described in any of the preceding embodiments, which will not be repeated here.

[0105] It should be noted that the miniature light-emitting diode display 1 or display device can be applied to augmented reality (AR) display devices, virtual reality (VR) display devices, near-eye display (NED) devices, head-up display (HUD) devices, and other similar devices.

[0106] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A miniature light-emitting diode display, characterized in that, include: substrate; The first LED unit layer, fused and bonded to the top of the substrate, includes a plurality of first LED units arranged at intervals, wherein the first LED units emit light of a first color; The second LED unit layer, fused and bonded above the first LED unit layer, includes a plurality of second LED units arranged at intervals, the second LED units emitting a second color light; the color conversion layer includes a plurality of color conversion units arranged at intervals, the color conversion units being disposed above the corresponding second LED units, used to convert the corresponding second color light into a third color light; or, the color conversion units penetrate the second LED unit layer and are disposed above the corresponding first LED units, used to convert the corresponding first color light into a third color light, the first color light, the second color light, and the third color light being different; at least one first LED unit, at least one adjacent second LED unit, and at least one adjacent color conversion unit constitute a full-color pixel.

2. The miniature light-emitting diode display according to claim 1, characterized in that, The first LED unit layer further includes a first leveling layer, which fills the spaces between adjacent first LED units and is fused to the substrate to create a gap between the first LED units and the substrate; the micro LED display further includes a first planarization layer, which is disposed above the first LED unit layer; the second LED unit layer further includes a second leveling layer, which fills the spaces between adjacent second LED units and is fused to the first planarization layer to create a gap between the second LED units and the first planarization layer.

3. The miniature light-emitting diode display according to claim 1, characterized in that, The first LED unit layer further includes a first leveling layer and a first bonding layer. The first leveling layer fills the spaces between adjacent first LED units and is fused to the substrate through the first bonding layer. The micro LED display further includes a first planarization layer disposed above the first LED unit layer. The second LED unit layer further includes a second leveling layer and a second bonding layer. The second leveling layer fills the spaces between adjacent second LED units and is fused to the first planarization layer through the second bonding layer.

4. The miniature light-emitting diode display according to claim 1, characterized in that, The first LED unit and the second LED unit each include a first doped semiconductor layer, an active layer, and a second doped semiconductor layer. The micro LED display further includes: a first electrode layer disposed above the first LED unit and electrically connected to the second doped semiconductor layer of the first LED unit; a second electrode layer disposed above the second LED unit and connected to the second doped semiconductor layer of the second LED unit; and a common conductive pillar for electrically connecting to an adjacent first electrode layer and / or an adjacent second electrode layer; wherein the color conversion unit is disposed on the upper surface of the first electrode layer or the second electrode layer.

5. The miniature light-emitting diode display according to claim 4, characterized in that, The substrate includes a plurality of first contacts, and the micro light-emitting diode display further includes: a first conductive structure electrically connected to the first doped semiconductor layer of the first LED unit; a first conductive post penetrating the first LED unit layer for electrically connecting the first conductive structure and the corresponding first contact; a second conductive structure electrically connected to the first doped semiconductor layer of the second LED unit; and a second conductive post penetrating the first LED unit layer and the second LED unit layer for electrically connecting the second conductive structure and the corresponding first contact.

6. The miniature light-emitting diode display according to claim 5, characterized in that, The first conductive structure includes a first conductive layer disposed below the first LED unit; the second conductive structure includes a second conductive layer disposed below the second LED unit.

7. The miniature light-emitting diode display according to claim 5, characterized in that, The first conductive structure includes a first conductive reflective cup, which surrounds the side and bottom of the first LED unit; the second conductive structure includes a second conductive reflective cup, which surrounds the side and bottom of the second LED unit.

8. The miniature light-emitting diode display according to claim 7, characterized in that, The first LED unit layer further includes a first passivation layer, which is disposed at least between the first LED unit and the first conductive reflective cup; the second LED unit layer further includes a second passivation layer, which is disposed at least between the second LED unit and the second conductive reflective cup.

9. The miniature light-emitting diode display according to claim 4, characterized in that, Also includes: The second planarization layer is disposed above the second LED unit layer; A filling hole extends at least through the second planarization layer and the second LED unit layer, and exposes the upper surface of the corresponding first electrode layer; a reflective metal layer is disposed on the inner wall of the filling hole and connected to the corresponding first electrode layer; wherein the color conversion unit is formed in the filling hole and covers the reflective metal layer.

10. The miniature light-emitting diode display according to claim 4, characterized in that, Also includes: A second planarization layer is disposed above the second LED unit layer; a color conversion adhesive layer is disposed above the second planarization layer; A filling hole penetrates the color conversion adhesive layer and the second planarization layer, and exposes the upper surface of the corresponding second electrode layer; a reflective metal layer is disposed on the inner wall of the filling hole and connected to the corresponding second electrode layer; wherein, the color conversion unit is formed in the filling hole and covers the reflective metal layer.

11. The miniature light-emitting diode display according to claim 4, characterized in that, Also includes: The filling hole penetrates at least through the second LED unit layer and exposes the upper surface of the corresponding first electrode layer; A reflective metal layer is disposed on the inner wall of the filling hole and connected to the corresponding first electrode layer; wherein, the color conversion unit is formed in the filling hole and covers the reflective metal layer.

12. The miniature light-emitting diode display according to claim 4, characterized in that, Also includes: A color conversion adhesive layer is disposed above the second LED unit layer; a filling hole penetrates the color conversion adhesive layer and exposes the upper surface of the corresponding second electrode layer; A reflective metal layer is disposed on the inner wall of the filling hole and connected to the corresponding second electrode layer; wherein the color conversion unit is formed in the filling hole and covers the reflective metal layer.

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