A light-emitting diode structure and fabrication method

Abstract

This invention relates to a light-emitting diode (LED) structure and its fabrication method. The invention includes a substrate, a back reflector, a buffer layer, a first semiconductor layer, an active layer, and a second semiconductor layer. A Mesa structure extending from the second semiconductor layer to the first semiconductor layer is disposed along the second semiconductor layer. The Mesa structure includes a stepped surface and a groove that exposes a portion of the first semiconductor layer. A transparent conductive layer is disposed on the second semiconductor layer. A current-blocking layer includes a first insulating layer and a second insulating layer. A first pad and a second pad are present, with the first pad partially penetrating the transparent conductive layer and the first insulating layer and contacting the transparent conductive layer, the first insulating layer, and the second semiconductor layer, respectively. The second pad partially contacts the bottom wall of the groove. A second insulating layer is at least partially disposed on the transparent conductive layer. Multiple microdisk resonant cavity structures are distributed on the surface of the second insulating layer and contact the surface of the transparent conductive layer through micropores. By introducing the microdisk resonant cavity structure, the optical coupling efficiency and light extraction efficiency are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a light-emitting diode structure and its fabrication method. Background Technology

[0002] Light-emitting diodes (LEDs) are widely used in lighting, displays, communications, and other fields due to their advantages such as high efficiency, energy saving, long lifespan, and environmental friendliness. With the continuous growth of market demand, higher requirements are being placed on LED performance, especially in terms of luminous efficacy and energy efficiency. Improving the light output efficiency of LEDs can not only reduce energy consumption but also enhance their competitiveness in various applications.

[0003] The light output efficiency of an LED is mainly determined by two parts: internal quantum efficiency and light extraction efficiency. Internal quantum efficiency relates to the efficiency of carrier injection and photon generation, while light extraction efficiency relates to the efficiency of photon transmission from inside the LED chip to the external environment. Currently, despite significant progress in internal quantum efficiency, light extraction efficiency remains one of the key bottlenecks limiting the overall light output efficiency of LEDs. Existing LED optical coupling structures offer limited efficiency improvements within specific wavelength ranges, failing to meet the demands for high-efficiency light output. Furthermore, some optimization methods require complex manufacturing processes, increasing production costs and process difficulty, which is detrimental to large-scale mass production. Summary of the Invention

[0004] Therefore, the present invention provides a light-emitting diode structure and manufacturing method, which significantly improves optical coupling efficiency and light extraction efficiency by introducing a micro disk resonant cavity structure.

[0005] To solve the above-mentioned technical problems, the present invention provides a light-emitting diode structure, comprising:

[0006] Substrate;

[0007] A back reflector is disposed on the back side of the substrate;

[0008] An epitaxial structure includes a buffer layer, a first semiconductor layer, an active layer, and a second semiconductor layer sequentially disposed along the front side of the substrate; wherein a Mesa structure extending to the first semiconductor layer is disposed along the second semiconductor layer, the Mesa structure including a stepped surface and a groove that expose a portion of the first semiconductor layer;

[0009] A transparent conductive layer is disposed on the second semiconductor layer;

[0010] The current blocking layer includes a first insulating layer one disposed on a portion of the surface of the second semiconductor layer and a first insulating layer two disposed on the bottom wall of the groove.

[0011] The first pad and the second pad are respectively connected. The first pad partially penetrates the transparent conductive layer and the first insulating layer and contacts the transparent conductive layer, the first insulating layer and the second semiconductor layer. The second pad is disposed above the first insulating layer and partially contacts the bottom wall of the groove.

[0012] A second insulating layer is at least partially disposed on the transparent conductive layer, wherein the second insulating layer has micropores extending to the surface of the transparent conductive layer;

[0013] Multiple microdisk resonant cavity structures are distributed on the surface of the second insulating layer and contact the surface of the transparent conductive layer through the micropores, wherein the refractive index of both the transparent conductive layer and the microdisk resonant cavity structures is greater than that of the second insulating layer.

[0014] In one embodiment of the present invention, the refractive index of the transparent conductive layer is 2.0 to 2.1; the refractive index of the microdisk resonant cavity structure is 1.9 to 2.5; and the refractive index of the second insulating layer is 1.4 to 1.6.

[0015] In one embodiment of the present invention, the material of the microdisk resonant cavity structure includes ITO (i.e., InSnO), Al2O3, Nb2O5 or HfO2.

[0016] In one embodiment of the present invention, both the current blocking layer and the second insulating layer are made of SiO2.

[0017] In one embodiment of the present invention, the material of the transparent conductive layer is ITO (i.e., InSnO).

[0018] In one embodiment of the present invention, the aperture of the micropore is 2 to 10 μm; the width of the microdisk resonant cavity structure is 20 to 50 μm; the thickness of the microdisk resonant cavity structure is 10 to 50 nm; and the spacing between two adjacent microdisk resonant cavity structures is 20 to 50 μm.

[0019] In one embodiment of the present invention, the shape of the microdisk resonant cavity structure includes a circle or a triangle;

[0020] The multiple microdisk resonant cavity structures are linearly distributed in the transverse and longitudinal directions of the light-emitting diode structure;

[0021] When the shape of the microdisk resonant cavity structure is circular, the multiple microdisk resonant cavity structures are symmetrically distributed along the symmetrical longitudinal section of the light-emitting diode structure;

[0022] When the microdisk resonant cavity structure is triangular in shape, the tips of all the triangles point in the same direction, or the tips of every two rows of triangles on both sides of the symmetrical longitudinal section of the light-emitting diode structure are opposite to each other.

[0023] In one embodiment of the present invention, the second insulating layer covers the surface of the transparent conductive layer, the stepped surface, and the exposed surface of the groove; or, the second insulating layer is respectively provided below each of the micro disk resonant cavity structures, and the edge of each second insulating layer is provided with a step.

[0024] In one embodiment of the present invention, the bottom wall and sidewalls of the micropore are provided with metal nanoparticles, the size of which is 0.5 to 5 nm, and the metal nanoparticles are metals with resonance peaks in the visible light range.

[0025] The present invention also provides a method for fabricating a light-emitting diode structure, comprising:

[0026] Provide substrate;

[0027] An epitaxial structure is fabricated on the front side of the substrate, comprising a buffer layer, a first semiconductor layer, an active layer, and a second semiconductor layer grown sequentially.

[0028] A Mesa structure is etched on the epitaxial structure to expose a portion of the first semiconductor layer. The Mesa structure includes a stepped surface and a groove.

[0029] Fabricating a current blocking layer includes fabricating a first insulating layer one on a portion of the surface of the second semiconductor layer and fabricating a first insulating layer two on the bottom wall of the groove;

[0030] A transparent conductive layer is fabricated on the second semiconductor layer;

[0031] A second insulating layer is formed on the transparent conductive layer, and micropores extending to the surface of the transparent conductive layer are formed on the second insulating layer;

[0032] After depositing oxide by sputtering, a pattern is fabricated to form a microdisk resonant cavity structure. Multiple microdisk resonant cavity structures are distributed on the surface of the second insulating layer and contact the surface of the transparent conductive layer through the micropores.

[0033] A pad area is formed on the second insulating layer, and a first pad and a second pad are correspondingly fabricated. The first pad partially penetrates the transparent conductive layer and the first insulating layer and contacts the transparent conductive layer, the first insulating layer and the second semiconductor layer respectively. The second pad is disposed above the second insulating layer and partially contacts the bottom wall of the groove.

[0034] The substrate is thinned, and a back reflector is fabricated on the back side of the substrate;

[0035] Cut to form individual components.

[0036] The technical solution of the present invention has the following advantages compared with the prior art:

[0037] This invention discloses a light-emitting diode (LED) structure and fabrication method. By setting a microdisk resonant cavity structure, photon coupling in the light-emitting region can be effectively enhanced, thereby improving internal quantum efficiency and overall light output efficiency. Through rational design of the refractive index matching and structural shape of the resonant cavity, internal light reflection and absorption are minimized, significantly improving light extraction efficiency. The material selection for the microdisk resonant cavity structure is flexible (such as ITO, Al2O3, Nb2O5, or HfO2), and optical performance can be optimized according to specific needs, further improving LED performance.

[0038] The light-emitting diode structure of the present invention adopts conventional semiconductor processes during manufacturing, avoiding complex process steps, reducing production costs and process difficulty, and facilitating large-scale mass production.

[0039] This invention uses SiO2 as the current blocking layer and insulating layer material, which ensures the stability and reliability of the LED structure and extends the device life. Attached Figure Description

[0040] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0041] Figure 1 This is a schematic diagram of the main structure of the light-emitting diode in Embodiment 1 of the present invention.

[0042] Figure 2 This is a top view schematic diagram of the light-emitting diode structure in Embodiment 1 of the present invention.

[0043] Figure 3 This is a schematic diagram of the distribution of the microdisk resonant cavity structure in Embodiment 2 of the present invention.

[0044] Figure 4 This is a schematic diagram of the distribution of the microdisk resonant cavity structure in Embodiment 3 of the present invention.

[0045] Figure 5 This is another schematic diagram of the distribution of the microdisk resonant cavity structure in Embodiment 3 of the present invention.

[0046] Figure 6 This is a schematic diagram of the light-emitting diode structure in Embodiment 4 of the present invention.

[0047] Figure 7This is a schematic diagram of the light-emitting diode structure in Embodiment 5 of the present invention.

[0048] Figure 8 yes Figure 7 A magnified view of a portion of the image.

[0049] Explanation of reference numerals on the accompanying drawings:

[0050] 1. Substrate;

[0051] 21. Buffer layer; 22. First semiconductor layer; 23. Active layer; 24. Second semiconductor layer; 25. Stepped surface; 26. Groove; 27. Back reflector;

[0052] 3. Transparent conductive layer;

[0053] 41. First insulating layer one; 42. First insulating layer two;

[0054] 51. First pad; 52. Second pad;

[0055] 6. Second insulating layer;

[0056] 7. Microdisk resonant cavity structure;

[0057] 8. Metal nanoparticles. Detailed Implementation

[0058] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0059] In this invention, when directions (up, down, left, right, front, and back) are described, it is only for the convenience of describing the technical solution of this invention, and does not indicate or imply that the technical features referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0060] In this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number; "above," "below," "within," etc., are understood to include the stated number. In the description of this invention, the terms "first" and "second" are used only to distinguish technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0061] In this invention, unless otherwise explicitly defined, the terms "setting," "installing," and "connecting" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; a fixed connection, a detachable connection, or an integrally formed connection; a mechanical connection, an electrical connection, or a connection capable of mutual communication; or the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this invention based on the specific content of the technical solution.

[0062] Example 1

[0063] Reference Figure 1 , Figure 2 As shown, a light-emitting diode structure in this embodiment includes:

[0064] Substrate 1;

[0065] Back reflector 27 is disposed on the back side of the substrate 1;

[0066] The epitaxial structure includes a buffer layer 21, a first semiconductor layer 22, an active layer 23, and a second semiconductor layer 24 sequentially disposed along the front side of the substrate 1; wherein a Mesa structure extending to the first semiconductor layer 22 is disposed along the second semiconductor layer 24, and the Mesa structure includes a stepped surface 25 and a groove 26 that expose a portion of the first semiconductor layer 22.

[0067] A transparent conductive layer 3 is disposed on the second semiconductor layer 24;

[0068] The current blocking layer includes a first insulating layer 41 disposed on a portion of the surface of the second semiconductor layer 24 and a second insulating layer 42 disposed on the bottom wall of the groove 26.

[0069] First pad 51 and second pad 52 (positive and negative electrode pads). The first pad 51 partially penetrates the transparent conductive layer 3 and the first insulating layer 41 and contacts the transparent conductive layer 3, the first insulating layer 41 and the second semiconductor layer 24 respectively. The second pad 52 is disposed above the first insulating layer 42 and partially contacts the bottom wall of the groove 26.

[0070] The second insulating layer 6 is at least partially disposed on the transparent conductive layer 3, wherein the second insulating layer 6 has micropores extending to the surface of the transparent conductive layer 3;

[0071] Multiple microdisk resonant cavity structures 7 are distributed on the surface of the second insulating layer 6 and contact the surface of the transparent conductive layer 3 through the micropores, wherein the refractive index of both the transparent conductive layer 3 and the microdisk resonant cavity structures 7 is greater than that of the second insulating layer 6.

[0072] Specifically, the refractive index of the transparent conductive layer 3 is between 2.0 and 2.1; the refractive index of the microdisk resonant cavity structure 7 is between 1.9 and 2.5; and the refractive index of the second insulating layer 6 is between 1.4 and 1.6.

[0073] Specifically, the material of the microdisk resonant cavity structure 7 includes ITO (i.e., InSnO), Al2O3, Nb2O5, or HfO2.

[0074] Both the current blocking layer and the second insulating layer 6 are made of SiO2.

[0075] The transparent conductive layer 3 is made of ITO (i.e., InSnO).

[0076] Specifically, the pore size L of the micropore S The width L of the microdisk resonant cavity structure 7 is between 2 and 10 μm. d The thickness of the microdisk resonant cavity structure 7 is 10-50 nm, and the spacing between two adjacent microdisk resonant cavity structures 7 is 20-50 nm.

[0077] Specifically, the second insulating layer 6 covers the surface of the transparent conductive layer 3, the stepped surface 25, and the exposed surface of the groove 26.

[0078] In this embodiment, the first pad 51 and the second pad 52 are made of metal, such as aluminum (Al) or gold (Au); the substrate 1 is made of sapphire; the buffer layer 21 is made of undoped gallium nitride (u-GaN); the first semiconductor layer 22 is made of n-type gallium nitride (n-GaN); the active layer 23 is a multiple quantum well (MQW); the second semiconductor layer 24 is made of p-type gallium nitride (p-GaN); and the back reflector 27 is a distributed Bragg reflector (DBR), which is typically an alternating stack of high-refractive-index and low-refractive-index materials, such as silicon dioxide (SiO2) and silicon nitride (Si3N4).

[0079] By rationally configuring the high-refractive-index transparent conductive layer 3 and the microdisk resonant cavity structure 7, the coupling of light in the resonant cavity region is enhanced, significantly improving the overall light extraction efficiency. The combination of refractive indices of the transparent conductive layer 3 (ITO), the microdisk resonant cavity material (such as Al2O3), and the insulating layer (SiO2) effectively reduces light reflection loss and improves light transmission efficiency.

[0080] Example 2

[0081] Reference Figure 3As shown, this embodiment provides a light-emitting diode structure. Compared with embodiment 1, the micro-disk resonant cavity in this light-emitting diode structure is circular in shape, and the multiple micro-disk resonant cavity structures 7 are linearly distributed in the transverse and longitudinal directions of the light-emitting diode structure; the multiple micro-disk resonant cavity structures 7 are symmetrically distributed along the symmetrical longitudinal section of the light-emitting diode structure.

[0082] The symmetry of a circular resonant cavity helps to distribute the light field evenly, reducing light spot unevenness and improving the light quality for display and lighting applications. A linearly distributed resonant cavity helps to even out heat distribution, improving the heat dissipation performance of LEDs and extending device lifespan.

[0083] The rest of the structure is the same as in Example 1.

[0084] Example 3

[0085] Reference Figure 4 As shown, this embodiment provides a light-emitting diode structure. Compared with embodiment 1, the microdisk resonant cavity in this light-emitting diode structure is triangular in shape, with all the apexes of the triangles pointing in the same direction.

[0086] Or, refer to Figure 5 As shown, the apexes of every two rows of triangles on either side of the symmetrical longitudinal section of the LED structure are opposite each other. This arrangement improves the concentration of light emission in the central area, enhances the focusing ability of light output, and increases the brightness and efficiency of the LED in a specific area.

[0087] The rest of the structure is the same as in Example 1.

[0088] Example 4

[0089] Reference Figure 6 As shown, this embodiment provides a light-emitting diode structure. Compared with embodiment 1, in this light-emitting diode structure, a second insulating layer 6 is respectively disposed below each of the microdisk resonant cavity structures 7, and a step is left at the edge of each second insulating layer 6. The above arrangement effectively reduces the absorption of SiO2 and further improves the light extraction efficiency.

[0090] The rest of the structure is the same as in Example 1.

[0091] Example 5

[0092] Reference Figure 7 , Figure 8 As shown, this embodiment provides a light-emitting diode structure. Compared with Embodiment 1, the bottom and sidewalls of the micropores in this light-emitting diode structure are provided with metal nanoparticles 8. The size of the metal nanoparticles 8 is 0.5-5 nm, and the metal nanoparticles 8 are metals with resonance peaks in the visible light range, such as Al, Ag, Pt, etc. The rest of the structure is the same as in Embodiment 1.

[0093] When fabricating the micropores of the second insulating layer 6, metal nanoparticles 8 are fabricated in the micropores using a self-assembly method. The metal nanoparticles 8 serve as resonant couplers, and by utilizing the local surface plasmon effect, the coupling efficiency between photons and the resonant cavity is further enhanced, significantly improving the light extraction efficiency.

[0094] Example 6

[0095] This embodiment provides a method for fabricating a light-emitting diode structure, including:

[0096] S1, providing substrate 1; such as sapphire;

[0097] S2. An epitaxial structure is fabricated on the front side of the substrate 1, including a buffer layer 21, a first semiconductor layer 22, an active layer 23, and a second semiconductor layer 24 sequentially grown by chemical vapor deposition (MOCVD); wherein, the buffer layer 21 is undoped gallium nitride (u-GaN); the first semiconductor layer 22 is n-type gallium nitride (n-GaN); the active layer 23 is a multiple quantum well (MQW); and the second semiconductor layer 24 is p-type gallium nitride (p-GaN);

[0098] S3. Etch (e.g., reactive ion etching or wet etching) a Mesa structure on the epitaxial structure and expose a portion of the first semiconductor layer 22 to define the light-emitting area and current channel of the LED; the Mesa structure includes a stepped surface 25 and a groove 26.

[0099] S4. Fabricating a current blocking layer, including fabricating a first insulating layer 41 on a portion of the surface of the second semiconductor layer 24 and a second insulating layer 42 on the bottom wall of the groove 26.

[0100] S5. A transparent conductive layer 3 is fabricated on the second semiconductor layer 24; the material of the transparent conductive layer 3 is ITO;

[0101] S6. A second insulating layer 6 is formed on the transparent conductive layer 3, and micropores extending to the surface of the transparent conductive layer 3 are formed on the second insulating layer 6. Step S6 may further include forming metal nanoparticles 8 in the micropores by self-assembly. The metal nanoparticles 8 are distributed on the bottom wall and side wall of the micropores. The size of the metal nanoparticles 8 is 0.5-5 nm. The metal nanoparticles 8 are metals with resonance peaks in the visible light range, such as Al, Ag and other metals. The metal atoms or molecules are self-assembled into nanoparticles in the micropores by chemical reduction or physical adsorption.

[0102] S7. After depositing a high-refractive-index oxide (ITO, Al2O3, Nb2O5, or HfO2) by sputtering, a pattern is fabricated to form the microdisk resonant cavity structure 7. High-vacuum magnetron sputtering equipment can be used to ensure high-quality thin film deposition. Photoresist is coated on the high-refractive-index oxide layer, and the pattern of the microdisk resonant cavity is transferred using photolithography. Reactive ion etching (RIE) or plasma etching techniques are used to precisely etch the microdisk-shaped resonant cavity structure.

[0103] When ITO is used, after sputtering deposition, a transparent conductive film needs to be formed by high-temperature alloying; wherein, multiple microdisk resonant cavity structures 7 are distributed on the surface of the second insulating layer 6 and contact the surface of the transparent conductive layer 3 through the micropores;

[0104] S8. A pad area is formed on the second insulating layer 6, and a first pad 51 and a second pad 52 are made accordingly. The first pad 51 partially penetrates the transparent conductive layer 3 and the first insulating layer 41 and contacts the transparent conductive layer 3, the first insulating layer 41 and the second semiconductor layer 24 respectively. The second pad 52 is disposed above the first insulating layer 42 and partially contacts the bottom wall of the groove 26.

[0105] S9. Thin the substrate 1 (mechanical grinding and chemical mechanical polishing) and fabricate a back reflector 27 (DBR) on the back side of the substrate 1 to improve light reflectivity and light output efficiency.

[0106] S10, cut into individual LED components, and then perform final packaging and testing.

[0107] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A light-emitting diode structure, characterized in that, include: Substrate (1); A back reflector (27) is disposed on the back side of the substrate (1); The epitaxial structure includes a buffer layer (21), a first semiconductor layer (22), an active layer (23), and a second semiconductor layer (24) disposed sequentially along the front side of the substrate (1); wherein a Mesa structure extending to the first semiconductor layer (22) is disposed along the second semiconductor layer (24), the Mesa structure including a stepped surface (25) and a groove (26) that exposes a portion of the first semiconductor layer (22). A transparent conductive layer (3) is disposed on the second semiconductor layer (24); The current blocking layer includes a first insulating layer (41) disposed on a portion of the surface of the second semiconductor layer (24) and a second insulating layer (42) disposed on the bottom wall of the groove (26). The first pad (51) and the second pad (52) are respectively connected. The first pad (51) partially penetrates the transparent conductive layer (3) and the first insulating layer (41) and contacts the transparent conductive layer (3), the first insulating layer (41) and the second semiconductor layer (24). The second pad (52) is disposed above the second insulating layer (42) and partially contacts the bottom wall of the groove (26). The second insulating layer (6) is at least partially disposed on the transparent conductive layer (3), wherein the second insulating layer (6) has micropores extending to the surface of the transparent conductive layer (3); Multiple microdisk resonant cavity structures (7) are distributed on the surface of the second insulating layer (6) and contact the surface of the transparent conductive layer (3) through the micropores, wherein the refractive index of the transparent conductive layer (3) and the microdisk resonant cavity structure (7) is greater than that of the second insulating layer (6).

2. The light-emitting diode structure according to claim 1, characterized in that, The refractive index of the transparent conductive layer (3) is 2.0 to 2.1; the refractive index of the microdisk resonant cavity structure (7) is 1.9 to 2.5; and the refractive index of the second insulating layer (6) is 1.4 to 1.

6.

3. The light-emitting diode structure according to claim 1, characterized in that, The materials of the microdisk resonant cavity structure (7) include ITO, Al2O3, Nb2O5 or HfO2.

4. A light-emitting diode structure according to claim 1, characterized in that, Both the current blocking layer and the second insulating layer (6) are made of SiO2.

5. A light-emitting diode structure according to claim 1, characterized in that, The transparent conductive layer (3) is made of ITO.

6. A light-emitting diode structure according to claim 1, characterized in that, The aperture of the micropore is 2~10um; the width of the microdisk resonant cavity structure (7) is 20~50um; the thickness of the microdisk resonant cavity structure (7) is 10~50nm; and the spacing between two adjacent microdisk resonant cavity structures (7) is 20~50um.

7. A light-emitting diode structure according to claim 1, characterized in that, The shape of the microdisk resonant cavity structure (7) includes a circle or a triangle; The multiple microdisk resonant cavity structures (7) are linearly distributed in the transverse and longitudinal directions of the light-emitting diode structure; When the shape of the micro disk resonant cavity structure (7) is circular, the multiple micro disk resonant cavity structures (7) are symmetrically distributed along the symmetrical longitudinal section of the light-emitting diode structure; When the microdisk resonant cavity structure (7) is triangular in shape, the tips of all the triangles face the same direction, or the tips of every two rows of triangles on both sides of the symmetrical longitudinal section of the light-emitting diode structure are opposite to each other.

8. A light-emitting diode structure according to claim 1, characterized in that, The second insulating layer (6) covers the surface of the transparent conductive layer (3), the stepped surface (25), and the exposed surface of the groove (26); or, the second insulating layer (6) is provided below each of the micro disk resonant cavity structures (7), and the edge of each second insulating layer (6) is left with a step.

9. A light-emitting diode structure according to claim 1, characterized in that, The bottom and sidewalls of the micropore are provided with metal nanoparticles (8), the size of which is 0.5~5nm, and the metal nanoparticles (8) are metals with resonance peaks in the visible light range.

10. A method for fabricating a light-emitting diode structure, characterized in that, include: Provide substrate (1); An epitaxial structure is fabricated on the front side of the substrate (1), including a buffer layer (21), a first semiconductor layer (22), an active layer (23), and a second semiconductor layer (24) grown sequentially. A Mesa structure is etched on the epitaxial structure to expose a portion of the first semiconductor layer (22). The Mesa structure includes a stepped surface (25) and a groove (26). Fabricating a current blocking layer includes fabricating a first insulating layer (41) on a portion of the surface of the second semiconductor layer (24) and fabricating a second insulating layer (42) on the bottom wall of the groove (26). A transparent conductive layer (3) is fabricated on the second semiconductor layer (24); A second insulating layer (6) is formed on the transparent conductive layer (3), and micropores extending to the surface of the transparent conductive layer (3) are formed on the second insulating layer (6); After depositing oxide by sputtering, a pattern is formed to create a micro disk resonant cavity structure (7). Multiple micro disk resonant cavity structures (7) are distributed on the surface of the second insulating layer (6) and contact the surface of the transparent conductive layer (3) through the micropores. A pad area is formed on the second insulating layer (6), and a first pad (51) and a second pad (52) are made accordingly. The first pad (51) partially penetrates the transparent conductive layer (3) and the first insulating layer (41) and contacts the transparent conductive layer (3), the first insulating layer (41) and the second semiconductor layer (24) respectively. The second pad (52) is disposed above the second insulating layer (42) and partially contacts the bottom wall of the groove (26). The substrate (1) is thinned and a back reflector (27) is fabricated on the back side of the substrate (1). Cut to form individual components.

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