Light emitting diode and light emitting device

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a light-emitting diode which comprises a first semiconductor layer, a light-emitting layer, a second semiconductor layer, a first coarsening structure and a second coarsening structure. The light-emitting layer is located on the first semiconductor layer, the upper surface, not covered by the light-emitting layer, of the first semiconductor layer is defined as a table top, the second semiconductor layer is located on the light-emitting layer, the first coarsening structure and the second coarsening structure are located below the first semiconductor layer, and the horizontal projection of the first coarsening structure is located in the horizontal projection of the light-emitting layer. The horizontal projection of the second coarsening structure is located in the horizontal projection of the table top, and the depth of the first coarsening structure is larger than that of the second coarsening structure. The lower surface of the first semiconductor layer corresponding to the light-emitting layer is provided with the larger first coarsening structure, and the lower surface of the first semiconductor layer corresponding to the table top is provided with the smaller second coarsening structure, so that the problem of large light-emitting intensity difference between the center and the edge of the chip can be solved, and the display requirement of uniform light pattern of the Micro LED chip is met.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a light emitting diode and a light emitting device. Background Art

[0002] Light Emitting Diode (LED) is a semiconductor light-emitting element, usually made of semiconductors such as GaN, GaAs, GaP, GaAsP, etc., and its core is a PN junction with light-emitting characteristics. LED has the advantages of high luminous intensity, high efficiency, small size, and long service life, and is considered to be one of the most promising light sources at present. LED has been widely used in lighting, monitoring and command, high-definition broadcasting, high-end cinemas, office displays, conference interaction, virtual reality and other fields.

[0003] In recent years, Micro LED chips, the ultimate display, have gradually become commercialized. In high-resolution display screens such as smartwatch displays and AR displays, the commercialization requirements for Micro LED chips are: the chip must emit light at a small angle perpendicular to the chip plane and the chip's light pattern must be uniform. However, the current Micro LED chips still have the problem of large differences in luminous intensity between the center and the edge, which cannot meet the display requirements of Micro LED chips for uniform light patterns. Therefore, how to ensure the uniform light pattern of Micro LED chips has become one of the technical problems that need to be solved urgently in this field.

[0004] It should be noted that the information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as admitting or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0005] The present invention provides a light emitting diode, which comprises a first semiconductor layer, a light emitting layer, a second semiconductor layer, a first roughening structure and a second roughening structure.

[0006] The first semiconductor layer has an upper surface and a lower surface relative to each other. The light-emitting layer is located on the upper surface of the first semiconductor layer, and the upper surface of the first semiconductor layer not covered by the light-emitting layer is defined as a table. The second semiconductor layer is located above the light-emitting layer. The first roughened structure is located on the lower surface of the first semiconductor layer. The second roughened structure is located on the lower surface of the first semiconductor layer. The horizontal projection of the first roughened structure is located within the horizontal projection of the light-emitting layer, the horizontal projection of the second roughened structure is located within the horizontal projection of the table, and the depth of the first roughened structure is greater than the depth of the second roughened structure.

[0007] The present invention also provides a light-emitting device, which includes a plurality of light-emitting diodes arranged in an array, with a spacing between the plurality of light-emitting diodes ranging from 0.1 to 10 μm, and each light-emitting diode adopts the light-emitting diode provided by any of the above embodiments.

[0008] A light-emitting diode and a light-emitting device provided by one embodiment of the present invention can solve the problem of large difference in luminous intensity between the center and edge of the chip by setting a larger and sparser first roughening structure on the lower surface of the first semiconductor layer corresponding to the light-emitting layer, and setting a smaller and denser second roughening structure on the lower surface of the first semiconductor layer corresponding to the table, thereby meeting the display requirements of the Micro LED chip with uniform light type.

[0009] Other features and beneficial effects of the present invention will be described in the following description, and some of the technical features and beneficial effects can be obviously derived from the description or understood by implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, some of the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0011] Figure 1 is a schematic diagram of the bottom structure of a light emitting diode provided by an embodiment of the present invention;

[0012] Figure 2 is along Figure 1 A schematic diagram of a cross-sectional structure taken along the interception line FF;

[0013] Figures 3 to 9 yes Figure 2 The schematic diagram of the structure of the light emitting diode at each stage in the manufacturing process is shown;

[0014] Fig.10 It is a schematic structural diagram of a light emitting diode provided in another embodiment of the present invention.

[0015] Reference numerals:

[0016] 10-first semiconductor layer; 101-upper surface; 102-lower surface; 103-table; 12-light-emitting layer; 14-second semiconductor layer; 16-first roughening structure; 161-first protrusion; 18-second roughening structure; 182-second protrusion; 20-transparent conductive layer; 21-first electrode; 22-second electrode; 24-insulating layer; 26-growth substrate; 30-sacrificial layer; 32-bonding layer; 34-transfer substrate; 41-first DBR structure; 42-second DBR structure; L1-first spacing; L2-second spacing; H1-depth of the first roughening structure; H2-depth of the second roughening structure; α-tilt angle. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments; the technical features designed in different implementation modes of the present invention described below can be combined with each other as long as they do not conflict with each other; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] In the description of the present invention, it should be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In addition, the term "including" and any variation thereof all mean "at least including".

[0019] See also Figure 1 and Figure 2 , Figure 1 is a schematic diagram of the bottom structure of a light emitting diode provided by an embodiment of the present invention, Figure 2 is along Figure 1FF is a cross-sectional structural diagram of the embodiment of the present invention. In order to achieve at least one of the above advantages or other advantages, an embodiment of the present invention provides a light emitting diode. As shown in the figure, the light emitting diode may include a first semiconductor layer 10, a light emitting layer 12, a second semiconductor layer 14, a first roughening structure 16 and a second roughening structure 18.

[0020] The first semiconductor layer 10 has an upper surface 101 and a lower surface 102 relative to each other. The first semiconductor layer 10 may be an N-type semiconductor layer, which may provide electrons to the light-emitting layer 12 under the action of a power source. In some embodiments, the first semiconductor layer 10 includes an N-type doped nitride layer. The N-type doped nitride layer may include N-type impurities. The N-type impurities may include one of Si, Ge, Sn or a combination thereof. The first semiconductor layer 10 may be a single-layer structure or a multi-layer structure, and the multi-layer structure has different compositions.

[0021] The light-emitting layer 12 is located on the upper surface 101 of the first semiconductor layer 10. The upper surface 101 of the first semiconductor layer 10 not covered by the light-emitting layer 12 is defined as a mesa 103 (mesa), and the mesa 103 of the first semiconductor layer 10 can be used for subsequent connection with the first electrode 21. The light-emitting layer 12 can be a quantum well structure (Quantum Well, referred to as QW). In some embodiments, the light-emitting layer 12 can also be a multiple quantum well structure (Multiple Quantum Well, referred to as MQW), wherein the multiple quantum well structure includes multiple quantum well layers (Well) and multiple quantum barrier layers (Barrier) alternately arranged in a repeated manner, for example, it can be a multiple quantum well structure of GaN / AlGaN, InAlGaN / InAlGaN or InGaN / AlGaN. In addition, the composition and thickness of the well layer in the light-emitting layer 12 determine the wavelength of the generated light. In order to improve the luminous efficiency of the light-emitting layer 12, it can be achieved by changing the depth of the quantum well, the number of layers, thickness and / or other characteristics of the paired quantum wells and quantum barriers in the light-emitting layer 12. In some embodiments, the light emitting diode has a plurality of hole-shaped mesa terraces 103 .

[0022] The second semiconductor layer 14 is located above the light emitting layer 12. The second semiconductor layer 14 may be a P-type semiconductor layer, which may provide holes to the light emitting layer 12 under the action of a power source. In some embodiments, the second semiconductor layer 14 includes a P-type doped nitride layer. The P-type doped nitride layer may include one or more P-type impurities. The P-type impurities may include one or a combination of Mg, Zn, and Be. The second semiconductor layer 14 may be a single-layer structure or a multi-layer structure, and the multi-layer structure has different compositions. In addition, the setting of the epitaxial structure is not limited thereto, and other types of epitaxial structures may be selected according to actual needs.

[0023] The first roughened structure 16 and the second roughened structure 18 are both located on the lower surface 102 of the first semiconductor layer 10, but are distributed in different regions. The horizontal projection of the first roughened structure 16 is located within the horizontal projection of the light-emitting layer 12, and the horizontal projection of the second roughened structure 18 is located within the horizontal projection of the table 103. Compared with the first roughened structure 16 and the second roughened structure 18, the first roughened structure 16 is a larger and sparser roughening, and the second roughened structure 18 is a smaller and denser roughening, so the depth H1 of the first roughened structure 16 is greater than the depth H2 of the second roughened structure 18. Since the smaller the roughening and the greater the density, the better the light emitting effect, a larger and sparser first roughening structure 16 is set on the lower surface 102 of the first semiconductor layer 10 corresponding to the light-emitting layer 12, and a smaller and denser second roughening structure 18 is set on the lower surface 102 of the first semiconductor layer 10 corresponding to the table 103. The problem of large difference in luminous intensity between the table 103 and the area with the light-emitting layer 12 due to the absence of the light-emitting layer 12 is solved, and the problem of large difference in luminous intensity between the center and the edge of the chip is solved, thereby meeting the display requirements of the Micro LED chip with uniform light type.

[0024] The so-called horizontal projection refers to the orthographic projection of the structure on the horizontal plane. Figure 1 From a 3D perspective, the first roughened structure 16 and the second roughened structure 18 shown in the figure are their corresponding horizontal projections, and the horizontal projection of the light-emitting layer 12 is in the A area circled by the dotted line box.

[0025] The first roughening structure 16 includes a plurality of first protrusions 161, and the second roughening structure 18 includes a plurality of second protrusions 182. The volume of the first protrusion 161 is greater than the volume of the second protrusion 182, so that the first roughening structure 16 is a larger and sparser roughening, and the second roughening structure 18 is a smaller and denser roughening, thereby improving the light uniformity of the light emitting diode. The first spacing L1 between the protrusion vertices of two adjacent first protrusions 161 is greater than the second spacing L2 between the protrusion vertices of two adjacent second protrusions 182, so that the first roughening structure 16 is a larger and sparser roughening, and the second roughening structure 18 is a smaller and denser roughening, thereby improving the light uniformity of the light emitting diode. The protrusion vertex of each protrusion refers to the end point away from the first semiconductor layer 10 (such as Figure 2 The lower end point of the first protrusion 161 and the lower end point of the second protrusion 182 in the embodiment of the present invention are as follows: (i) the lower end point of each protrusion may be a plane (e.g., the cross-sectional shape of the protrusion is similar to an inverted trapezoid), and the vertex of the protrusion in this case refers to the plane. Optionally, the first spacing L1 ranges from 0.1 to 3 μm, and may be 0.2 μm; optionally, the second spacing L2 ranges from 0.01 to 1.5 μm, which solves the problem of large difference in luminous intensity between the center and edge of the chip and meets the display requirements of uniform light type of the Micro LED chip.

[0026] The depth H1 of the first coarsening structure 16 is 1.05 to 2 times the depth H2 of the second coarsening structure 18, so that the first coarsening structure 16 is a larger and sparser coarsening, and the second coarsening structure 18 is a smaller and denser coarsening, thereby improving the light uniformity of the light emitting diode. In order to control the angle consistency and improve the performance of the light emitting diode, optionally, the depth H1 of the first coarsening structure 16 is 1.5 times the depth H2 of the second coarsening structure 18. If the difference between H1 and H2 is too large, the angle consistency of the first coarsening structure 16 and the second coarsening structure 18 will be difficult to control uniformly. Optionally, the angle difference between the first protrusion 161 and the second protrusion 182 is within a range of plus or minus 5°, or the angle difference between the first protrusion 161 and the second protrusion 182 is 2 to 4 times. Optionally, the depth H1 of the first roughened structure 16 ranges from 0.1 to 2 μm, and the depth H2 of the second roughened structure 18 ranges from 0.01 to 1 μm, which solves the problem of large difference in luminous intensity between the center and edge of the chip and meets the display requirements of the Micro LED chip for uniform light type.

[0027] In some embodiments, the inclination angle α of the first protrusion 161 ranges from 45° to 75°, which has a better effect on light emission and can make the light emit at a small angle as much as possible. Optionally, the diameter of the first protrusion 161 ranges from 0.5 to 2 μm, and the diameter of the second protrusion 182 ranges from 0.1 to 1 μm.

[0028] Considering that the mesa 103 of the light-emitting diode is formed by etching away part of the first semiconductor layer 10 using ICP, many recombination centers will be generated after the ICP etching, resulting in a very low luminous efficiency in the mesa 103 area. In particular, the closer the light-emitting layer 12 is to the mesa 103, the lower the luminous efficiency. Figure 2 The four B areas are circled with dotted lines in the figure. Therefore, a design of smaller coarsening and greater density is adopted near the mesa 103 to improve the light intensity so that the light intensity of the mesa 103 and non-mesa 103 areas is evenly distributed. That is, the horizontal projection of part of the second coarsening structure 18 is located within the horizontal projection of the edge area of ​​the light-emitting layer 12, the horizontal projection of the first coarsening structure 16 is all located within the horizontal projection of the light-emitting layer 12, the horizontal projection of the second coarsening structure 18 is partially located within the horizontal projection of the mesa 103, and the rest is located within the horizontal projection of the edge of the light-emitting layer 12. The edge area of ​​the light-emitting layer 12 refers to the area formed by each piece of the light-emitting layer 12 ( Figure 2 The outermost side of the two whole light-emitting layers 12 in the middle extends 0.1 to 2 μm into the interior of each light-emitting layer 12 to improve the uniform light emission performance of the light-emitting diode. If the area is larger than 2 μm, it will affect the overall light emission effect; if the area is smaller than 0.1 μm, the light emission effect of the edge area of ​​the light-emitting layer 12 is not good, resulting in uneven light emission of the light-emitting diode.

[0029] The light emitting diode may further include a transparent conductive layer 20 , an insulating layer 24 , a first electrode 21 and a second electrode 22 .

[0030] The transparent conductive layer 20 is located on the second semiconductor layer 14. The transparent conductive layer 20 is made of a transparent conductive material, which may include indium tin oxide (ITO), indium zinc oxide (IZO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium doped zinc oxide (GZO), tungsten doped indium oxide (IWO) or zinc oxide (ZnO), but the embodiments of the present disclosure are not limited thereto.

[0031] The insulating layer 24 covers the first semiconductor layer 10, the light emitting layer 12, the second semiconductor layer 14 and the transparent conductive layer 20. The insulating layer 24 has a first opening and a second opening. The first opening exposes the first semiconductor layer 10, and the second opening exposes the transparent conductive layer 20. The insulating layer 24 has different functions according to the positions involved. For example, when the insulating layer 24 covers the sidewalls of the first semiconductor layer 10 and the second semiconductor layer 14, it can be used to prevent the first semiconductor layer 10 and the second semiconductor layer 14 from being electrically connected due to leakage of conductive materials, thereby reducing the short circuit anomaly of the light emitting diode, but the embodiments of the present disclosure are not limited thereto. The material of the insulating layer 24 includes a non-conductive material. The non-conductive material is preferably an inorganic material or a dielectric material. The inorganic material may include silica gel. The dielectric material includes an electrically insulating material such as aluminum oxide, silicon nitride, silicon oxide, titanium oxide, or magnesium fluoride. For example, the insulating layer 24 may be silicon dioxide, silicon nitride, titanium oxide, tantalum oxide, niobium oxide, barium titanate, or a combination thereof, and the combination thereof may be, for example, a Bragg reflector (DBR) formed by repeatedly stacking two materials with different refractive indices.

[0032] The first electrode 21 is electrically connected to the first semiconductor layer 10 through the first opening. The first electrode 21 can be a single-layer, double-layer or multi-layer structure, for example, a stacked structure of Ti / Al, Ti / Al / Ti / Au, Ti / Al / Ni / Au, V / Al / Pt / Au, etc.

[0033] The second electrode 22 is electrically connected to the transparent conductive layer 20 through the second opening. The second electrode 22 can be a single-layer, double-layer or multi-layer structure, for example, a stacked structure of Ti / Al, Ti / Al / Ti / Au, Ti / Al / Ni / Au, V / Al / Pt / Au, etc.

[0034] See also Figures 3 to 9 , Figures 3 to 9 yes Figure 2 The structure diagram of the light emitting diode at each stage of the manufacturing process is shown below. Figure 2 The light emitting diode method is shown.

[0035] First, if Figure 3 As shown, a first semiconductor layer 10, a light emitting layer 12 and a second semiconductor layer 14 are sequentially deposited on a growth substrate 26. The first semiconductor layer 10, the light emitting layer 12 and the second semiconductor layer 14 are partially etched to expose the mesa 103 of the first semiconductor layer 10.

[0036] Secondly, if Figure 4 As shown, a transparent conductive layer 20 is formed on the second semiconductor layer 14 .

[0037] Then, if Figure 5 As shown, an insulating layer 24 is deposited on the first semiconductor layer 10 and the second semiconductor layer 14, and the insulating layer 24 covers the first semiconductor layer 10, the light emitting layer 12, the second semiconductor layer 14 and the transparent conductive layer 20. The insulating layer 24 has a first opening and a second opening. The first opening exposes the first semiconductor layer 10, and the second opening exposes the transparent conductive layer 20.

[0038] Continue, such as Figure 6 As shown, a first electrode 21 and a second electrode 22 are formed on the insulating layer 24. The first electrode 21 is connected to the first semiconductor layer 10 through the first opening. The second electrode 22 is connected to the transparent conductive layer 20 through the second opening.

[0039] Then, if Figure 7 As shown, a sacrificial layer 30 (Sacrificial Layer), a bonding layer 32 and a transfer substrate 34 are sequentially arranged above the insulating layer 24, the first electrode 21 and the second electrode 22.

[0040] Then, if Figure 8As shown, the growth substrate 26 located on the lower surface 102 of the first semiconductor layer 10 is removed, and the lower surface 102 of the first semiconductor layer 10 is subjected to a surface roughening treatment. That is, a larger and sparser first roughening structure 16 is formed by the roughening treatment on the lower surface 102 of the first semiconductor layer 10 corresponding to the light-emitting layer 12, a smaller and denser second roughening structure 18 is formed by the roughening treatment on the lower surface 102 of the first semiconductor layer 10 corresponding to the mesa 103, and a smaller and denser second roughening structure 18 is also formed on the lower surface 102 of the first semiconductor layer 10 corresponding to the edge region of the light-emitting layer 12.

[0041] Finally, if Fig. 9 As shown, sacrificial layer 30, bonding layer 32, and transfer substrate 34 are removed.

[0042] The above is only a public one for making Figure 2 The method of manufacturing a light emitting diode shown in the figure is not limited to the present invention, but is only used to illustrate a method of manufacturing a light emitting diode.

[0043] See also Fig.10 , Fig.10 is a schematic diagram of the structure of a light emitting diode provided by another embodiment of the present invention. Figure 2 As for the light-emitting diode shown in the figure, the main difference of the light-emitting diode of this embodiment is that the light-emitting diode also includes a first DBR structure 41 and a second DBR structure 42. The first DBR structure 41 covers the first roughening structure 16 in an intermittent manner, and the first DBR structure 41 is separated by a first protrusion 161, that is, there is a first protrusion 161 between two adjacent first DBR structures 41. The second DBR structure 42 covers the second roughening structure 18 in an intermittent manner, and the second DBR structure 42 is separated by a second protrusion 182, that is, there is a second protrusion 182 between two adjacent second DBR structures 42. By setting the first DBR structure 41 and the second DBR structure 42, light can be emitted from the interval opening of the first DBR structure 41 and the second DBR structure 42, thereby forming a small-angle vertical light emission, which meets the light-emitting diode's demand for small-angle vertical light emission.

[0044] In some embodiments, the size of the light emitting diode is less than or equal to 50 μm, that is, the light emitting diode is suitable for small size, such as Micro LED. The size of the light emitting diode is the length or width of the light emitting diode.

[0045] The present invention also provides a light-emitting device, which includes a plurality of light-emitting diodes arranged in an array, with a spacing between the plurality of light-emitting diodes ranging from 0.1 to 10 μm, and each light-emitting diode adopts the light-emitting diode provided by any of the above embodiments.

[0046] A light-emitting diode and a light-emitting device provided in one embodiment of the present invention can solve the problem of large difference in luminous intensity between the center and edge of the chip by setting a larger and sparser first roughening structure 16 on the lower surface 102 of the first semiconductor layer 10 corresponding to the light-emitting layer 12, and setting a smaller and denser second roughening structure 18 on the lower surface 102 of the first semiconductor layer 10 corresponding to the table 103, thereby meeting the display requirements of the Micro LED chip with uniform light type.

[0047] In addition, those skilled in the art should understand that, although there are many problems in the prior art, each embodiment or technical solution of the present invention can be improved in only one or several aspects, without having to solve all the technical problems listed in the prior art or background technology at the same time. Those skilled in the art should understand that the content not mentioned in a claim should not be used as a limitation on the claim.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A light emitting diode, characterized in that: The light emitting diode comprises: a first semiconductor layer having an upper surface and a lower surface opposite to each other; A light-emitting layer is located on the upper surface of the first semiconductor layer, and the upper surface of the first semiconductor layer not covered by the light-emitting layer is defined as a mesa; A second semiconductor layer, located on the light-emitting layer; A first roughening structure is located on the lower surface of the first semiconductor layer; A second roughening structure is located on the lower surface of the first semiconductor layer; The horizontal projection of the first roughened structure is located within the horizontal projection of the light-emitting layer, the horizontal projection of the second roughened structure is located within the horizontal projection of the mesa, and the depth of the first roughened structure is greater than the depth of the second roughened structure.

2. The light emitting diode according to claim 1, characterized in that: The first roughening structure includes a plurality of first protrusions, the second roughening structure includes a plurality of second protrusions, the volume of the first protrusions is greater than the volume of the second protrusions, and a first spacing between protrusion vertices of two adjacent first protrusions is greater than a second spacing between protrusion vertices of two adjacent second protrusions.

3. The light emitting diode according to claim 2, characterized in that: The first spacing ranges from 0.1 to 3 μm.

4. The light emitting diode according to claim 2, characterized in that: The second spacing ranges from 0.01 to 1.5 μm.

5. The light emitting diode according to claim 2, characterized in that: The inclination angle of the first protrusion ranges from 45° to 75°.

6. The light emitting diode according to claim 2, characterized in that: The light-emitting diode further includes a first DBR structure and a second DBR structure, wherein the first DBR structure covers the first roughening structure in an intermittent manner, and the first DBR structure is spaced apart from the first protrusion, and the second DBR structure covers the second roughening structure in an intermittent manner, and the second DBR structure is spaced apart from the second protrusion.

7. The light emitting diode according to claim 1, characterized in that: The horizontal projection of part of the second roughened structure is located within the horizontal projection of the edge region of the light-emitting layer. The edge region of the light-emitting layer refers to a region extending 0.1 to 2 μm from the side of the light-emitting layer to the inside of the light-emitting layer.

8. The light emitting diode according to claim 1, characterized in that: The depth of the first roughening structure is 1.05 to 2 times the depth of the second roughening structure.

9. The light emitting diode according to claim 1, characterized in that: The depth of the first roughened structure is in the range of 0.1 to 2 μm.

10. The light emitting diode according to claim 1, characterized in that: The depth of the second roughened structure is in the range of 0.01 to 1 μm.

11. The light emitting diode according to claim 1, characterized in that: The size of the light emitting diode is less than or equal to 50 μm.

12. The light emitting diode according to claim 1, characterized in that: The light-emitting diode also includes a transparent conductive layer, an insulating layer, a first electrode and a second electrode. The transparent conductive layer is located on the second semiconductor layer. The insulating layer covers the first semiconductor layer, the light-emitting layer, the second semiconductor layer and the transparent conductive layer. The insulating layer has a first opening and a second opening. The first electrode is electrically connected to the first semiconductor layer through the first opening, and the second electrode is electrically connected to the transparent conductive layer through the second opening.

13. A light emitting device, characterized in that: The light emitting device comprises a plurality of light emitting diodes arranged in an array, the spacing between the plurality of light emitting diodes is in the range of 0.1 to 10 μm, and each of the light emitting diodes is a light emitting diode as claimed in any one of claims 1 to 12.

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