Epitaxial structure and light-emitting diode

Abstract

The present application discloses an epitaxial structure and a light-emitting diode, comprising an n-type layer, a p-type layer, and an active layer. The active layer comprises a first concentration profile of In with a first peak shape; a heavily doped layer is located between the n-type layer and the active layer and comprises a second concentration profile of Si with a second peak shape; a current spreading layer is located between the heavily doped layer and the active layer and comprises a third concentration profile of In with a third peak shape; the minimum distance between the peak of the third peak shape and the peak of the first peak shape is D1, and the minimum distance between the peak of the third peak shape and the peak of the second peak shape is D2, and the ratio of D1 to D2 is less than 1:7. The current spreading layer is as close as possible to the active layer and effectively guides the impact current when subjected to electrostatic shock, protecting the active layer from electrostatic breakdown. Furthermore, the region between the current spreading layer and the heavily doped layer serves as an electron storage area, which reduces the risk of electrostatic breakdown of the epitaxial structure when subjected to electrostatic shock, thereby improving the anti-static capability of the epitaxial structure and the light-emitting diode.

Description

Technical Field

[0001] The present application relates to the field of semiconductor-related technologies, and in particular to an epitaxial structure and a light-emitting diode. Background Art

[0002] Group III nitrides, represented by gallium nitride (GaN), are direct-transition wide-bandgap semiconductor materials. They exhibit high thermal conductivity, high hardness, a low dielectric constant, high-temperature resistance, and acid and alkali resistance, making them widely used in blue, green, and ultraviolet light-emitting diodes. The epitaxial structure of a GaN-based LED comprises an n-type GaN layer, an active layer, and a p-type GaN layer. The active layer is a periodic structure composed of alternating GaN and InGaN (indium gallium nitride) layers. Due to the different lattice constants of the GaN and InGaN layers, polarization effects are likely to occur, leading to dislocation defects. If these dislocation defects are not effectively controlled, a large number of surface defects will form. Furthermore, the InGaN layer has a high indium concentration and requires low-temperature growth, during which surface defects will also form. These surface defects can create leakage channels and reduce the antistatic capability of the epitaxial structure. Summary of the Invention

[0003] The purpose of this application is to provide an epitaxial structure, which reduces the risk of electrostatic breakdown of the epitaxial structure by making the current spreading layer as close to the active layer as possible and providing an electron storage area with a large thickness between the current spreading layer and the heavily doped layer, thereby effectively improving the anti-static ability of the epitaxial structure.

[0004] Another object is to provide a light emitting diode comprising the above-mentioned epitaxial structure.

[0005] In a first aspect, an embodiment of the present application provides an epitaxial structure, comprising:

[0006] An n-type layer, a p-type layer, and an active layer located therebetween, the active layer comprising a first concentration profile of In, the first concentration profile comprising a plurality of first peaks;

[0007] a heavily doped layer located between the n-type layer and the active layer and comprising a second Si concentration profile, wherein the second Si concentration profile comprises a second peak;

[0008] The current spreading layer is located between the heavily interdoped layer and the active layer, and includes a third concentration profile of In, the third concentration profile includes a plurality of third peaks; the minimum distance between the peak top of the third peak and the peak top of the first peak is D1, the minimum distance between the peak top of the third peak and the peak top of the second peak is D2, and the ratio of D1 to D2 is less than 1:7.

[0009] In one possible embodiment, the minimum distance D1 between the peak top of the third peak shape and the peak top of the first peak shape is less than 20 nm.

[0010] In one possible embodiment, the minimum distance D2 between the peak top of the third peak shape and the peak top of the second peak shape is greater than 150 nm.

[0011] In a possible implementation, a first intermediate layer is included between the current spreading layer and the active layer, and a thickness of the first intermediate layer is less than a minimum distance D1 between the peak of the third peak shape and the peak of the first peak shape.

[0012] In one possible embodiment, the thickness of the first intermediate layer is equal to or greater than 80% of D1.

[0013] In one possible embodiment, the first intermediate layer is a Si-doped GaN layer, and the Si doping concentration is 1.5×10 17 ~5×10 17 cm -3 .

[0014] In a possible embodiment, a second intermediate layer is included between the current spreading layer and the heavily doped layer, and a thickness of the second intermediate layer is less than a minimum distance D2 between a peak of the third peak shape and a peak of the second peak shape.

[0015] In one possible embodiment, the thickness of the second intermediate layer is equal to or greater than 80% of D2.

[0016] In one possible embodiment, the second intermediate layer is a Si-doped GaN layer, and the Si doping concentration is 1×10 18 ~2×10 18 cm -3 .

[0017] In one possible embodiment, the doping concentration of the heavily doped layer is 1×10 18 ~6×10 18 cm -3 .

[0018] In one possible embodiment, the current spreading layer is a GaN layer and an In x Ga 1-x A periodic superlattice structure composed of N alternating layers, where 0≤x≤0.4.

[0019] In a possible implementation manner, the number of periods of the superlattice structure in the current spreading layer is 3-30.

[0020] In one possible embodiment, the thickness of the current spreading layer is greater than 30 nm and less than 80 nm.

[0021] In one possible embodiment, the thickness of the GaN layer in a single period of the superlattice structure is between 8 and 10 nm; the thickness of the In layer in a single period of the superlattice structure is between 8 and 10 nm.x Ga 1-x The thickness of the N layer is between 1 and 2 nm.

[0022] In one possible embodiment, the active layer is a multi-layer quantum well layer composed of In y Ga 1-y A periodic superlattice structure consisting of alternating N-well layers and GaN barrier layers; the In doping concentration in the active layer within a single period is greater than the In doping concentration in the current spreading layer within a single period.

[0023] In a second aspect, an embodiment of the present application provides a light emitting diode, which includes the epitaxial structure in the above embodiment.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] The present application adjusts the minimum distance D1 between the peak of the third peak and the peak of the first peak, so that the current spreading layer is as close to the active layer as possible, and can effectively guide the impact current when the epitaxial structure and the light-emitting diode using the epitaxial structure are subjected to electrostatic shock, thereby protecting the active layer from electrostatic breakdown; at the same time, the area between the current spreading layer and the heavily doped layer is an electron storage area, and the electron storage area has a large thickness. When subjected to electrostatic shock, the electron storage area can provide a large amount of electrons to reduce the risk of electrostatic breakdown of the epitaxial structure and the light-emitting diode using the epitaxial structure, thereby improving the anti-static ability of the epitaxial structure and the light-emitting diode using the epitaxial structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 Schematic diagram of an epitaxial structure according to an embodiment of the present application;

[0028] Figure 2 The relationship between the concentration or ion strength of some elements and depth in an epitaxial structure according to an embodiment of the present application is shown.

[0029] Illustration:

[0030] 10 substrate; 11 buffer layer; 12 n-type layer; 13 heavily doped layer; 14 current spreading layer; 15 active layer; 16 electron blocking layer; 17 p-type layer; 18 first intermediate layer; 19 second intermediate layer; 100 first concentration profile; 110 first peak shape; 200 second concentration profile; 210 second peak shape; 300 second concentration profile; 310 second peak shape; D1 minimum distance between the peak top of the third peak shape and the peak top of the first peak shape; D2 minimum distance between the peak top of the third peak shape and the peak top of the second peak shape. DETAILED DESCRIPTION

[0031] The following describes the implementation of the present application through specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present application from the disclosure herein. The present application may also be implemented or operated through various other specific implementations, and the details of the present application may be modified or altered based on different viewpoints and applications without departing from the spirit of the present application.

[0032] The composition of each layer included in the present application can be analyzed by any suitable method, such as secondary ion mass spectrometry (SIMS); the thickness of each layer can be analyzed by any suitable method, such as transmission electron microscopy (TEM) or scanning electron microscopy (SEM), to match the depth position of each layer on the SIMS map.

[0033] According to one aspect of the present application, an epitaxial structure is provided. Figure 1 and Figure 2 The epitaxial structure includes an n-type layer 12, a p-type layer 17, and an active layer 15 located therebetween. The active layer 15 includes a first concentration profile 100 of In, which includes a plurality of first peaks 110. The heavily doped layer 13 is located between the n-type layer 12 and the active layer 15 and includes a second concentration profile 200 of Si, which includes a second peak 210. The current spreading layer 14 is located between the heavily doped layer 13 and the active layer 15 and includes a third concentration profile 300 of In, which includes a plurality of third peaks 310. The minimum distance between the peaks of the third peaks 310 and the peaks of the first peaks 110 is D1, and the minimum distance between the peaks of the third peaks 310 and the peaks of the second peaks 210 is D2, and the ratio of D1 to D2 is less than 1:7.

[0034] By adjusting the minimum distance D1 between the peak of the third peak 310 and the peak of the first peak 110, the current spreading layer 14 is brought as close as possible to the active layer 15. This effectively guides the impact current when the epitaxial structure and the light-emitting diodes employing such structures are subjected to electrostatic shock, protecting the active layer 15 from electrostatic breakdown. Furthermore, the region between the current spreading layer 14 and the heavily doped layer 13 serves as an electron storage area, and this area has a large thickness. When subjected to electrostatic shock, this electron storage area can provide a large amount of electrons to offset the external electric field, reducing the risk of electrostatic breakdown in the epitaxial structure and the light-emitting diodes employing such structures, and improving the anti-static capability of the epitaxial structure and the light-emitting diodes employing such structures.

[0035] In one embodiment, see Figure 2 The minimum distance D1 between the peak top of the third peak 310 and the peak top of the first peak 110 is less than 20 nm. Preferably, the minimum distance D1 between the peak top of the third peak 310 and the peak top of the first peak 110 is less than 15 nm.

[0036] An example is given in which the first concentration profile 100 includes N first peaks 110 and the third concentration profile 300 includes three third peaks 310.

[0037] Depend on Figure 2 As can be seen, first concentration profile 100 includes N first peaks 110, which are sequentially defined along the direction of increasing depth as first peak I, first peak II, ..., first peak N. Third concentration profile 300 includes three third peaks 310, which are sequentially defined along the direction of increasing depth as third peak I, third peak II, and third peak III. Third peak I is closest to first peak N. Distance D1, the distance between the peak tops of third peak I and first peak N, is less than 20 nm.

[0038] A first intermediate layer 18 is included between the current spreading layer 14 and the active layer 15. The thickness of the first intermediate layer 18 is less than the distance D1. The distance D1 includes three parts, specifically the horizontal width D between the peak top of the third peak 310 and the peak bottom close to the first peak 110. 11 , the thickness D of the first intermediate layer 18 12 , and the horizontal width D between the peak top of the first peak 110 and the peak bottom close to the third peak 310 13 , the thickness D of the first intermediate layer 18 12 It is preferably equal to or greater than 80% of the above D1.

[0039] The first intermediate layer 18 is a Si-doped GaN layer, and the Si doping concentration is 1.5×10 17 ~5×10 17 cm-3 The first intermediate layer 18 has a relatively low thickness, ensuring that the current spreading layer 14 is as close as possible to the active layer 15. This allows the epitaxial structure and the light-emitting diodes employing the epitaxial structure to effectively guide the impact current when subjected to static electricity, protecting the active layer 15 from static electricity breakdown and improving the anti-static capabilities of the epitaxial structure and the light-emitting diodes employing the epitaxial structure. Furthermore, if the current spreading layer 14, heavily doped layer 13, or n-type layer 12 have growth defects, the first intermediate layer 18 can protect the active layer 15 from the effects of these growth defects, thereby improving the growth quality of the active layer 15.

[0040] In one embodiment, see Figure 2 The minimum distance D2 between the peak top of the third peak 310 and the peak top of the second peak 210 is greater than 150 nm. Preferably, the minimum distance D2 between the peak top of the third peak 310 and the peak top of the second peak 210 is greater than 200 nm.

[0041] Take the third concentration profile 300 including three third peaks 310 as an example for illustration:

[0042] Depend on Figure 2 As can be seen, second concentration profile 200 includes a second peak 210. Third concentration profile 300 includes three third peaks 310, which are defined as third peak I, third peak II, and third peak III, respectively, along the direction of increasing depth. Third peak III is closest to second peak 210. Distance D2, defined as the distance between the peak top of third peak III and the peak top of second peak 210, is greater than 150 nm.

[0043] A second intermediate layer 19 is included between the current spreading layer 14 and the heavily doped layer 13. The thickness of the second intermediate layer 19 is less than the distance D2. The distance D2 includes three parts, specifically the horizontal width D between the peak top of the third peak 310 and the peak bottom near the second peak 210. 21 , the thickness D of the second intermediate layer 19 22 and the horizontal width D between the peak top of the second peak 210 and the peak bottom close to the third peak 310. 23 , the thickness D of the second intermediate layer 19 22 It is preferably equal to or greater than 80% of the above D2.

[0044] The second intermediate layer 19 is a Si-doped GaN layer, and the Si doping concentration is 1×10 18 ~2×10 18 cm -3The second intermediate layer 19 is an electron storage area and has a large thickness. When the epitaxial structure and the light-emitting diode using the epitaxial structure are subjected to static electricity impact, the second intermediate layer 19 can provide a large number of electrons to offset the external electric field, thereby reducing the risk of electrostatic breakdown of the epitaxial structure and the light-emitting diode using the epitaxial structure, and improving the anti-static ability of the epitaxial structure and the light-emitting diode using the epitaxial structure.

[0045] In one embodiment, the current spreading layer 14 is a GaN layer and an In x Ga 1-x The periodic superlattice structure is composed of alternating N layers, where 0≤x≤0.4. The number of periods of the superlattice structure in the current spreading layer 14 is 3 to 30. In each period, the superlattice structure in the current spreading layer 14 is composed of GaN layer first and In layer second. x Ga 1-x The thickness of the GaN layer in a single cycle is between 8 and 10 nm, and the thickness of the In layer in a single cycle is between 8 and 10 nm. x Ga 1-x The thickness of the N layer is between 1 and 2 nm. The thickness of the current spreading layer 14 is preferably greater than 30 nm and less than 80 nm.

[0046] In one embodiment, the active layer 15 is a multi-layer quantum well layer composed of In y Ga 1-y The periodic superlattice structure is composed of alternating N potential well layers and GaN barrier layers, where 0≤y≤0.8. The number of periods of the superlattice structure in the active layer 15 is 6 to 20. The thickness of the GaN barrier layer in a single period is between 4 and 12 nm, and the thickness of the In layer in a single period is between 1 and 2 nm. y Ga 1-y The thickness of the N-well layer is between 2 and 4 nm.

[0047] Preferably, the doping concentration of In in the active layer 15 in a single cycle is greater than the doping concentration of In in the current spreading layer 14 in a single cycle, which can also be described as In y Ga 1-y The value of y in the N potential well layer is greater than In x Ga 1-x The value of x in the N layer.

[0048] In one embodiment, see Figure 1 The epitaxial structure further includes a substrate 10, which includes but is not limited to a sapphire substrate, a silicon carbide substrate, a silicon substrate or a gallium nitride substrate. The substrate 10 is preferably a sapphire substrate. A buffer layer 11 is formed on the substrate 10. The buffer layer 11 is an undoped GaN layer. The n-type layer 12 is formed on the side of the buffer layer 11 away from the substrate 10. The n-type layer 12 is a Si-doped GaN layer, and the Si doping concentration is 1×10 19 ~3×1019 cm -3 .

[0049] Preferably, an electron blocking layer 16 is further included between the active layer 15 and the p-type layer 17. The electron blocking layer 16 is a Mg-doped GaN layer with a Mg doping concentration of 1×10 18 ~3×10 18 cm -3 The p-type layer 17 is a Mg-doped GaN layer with a Mg doping concentration of 2×10 18 ~8×10 18 cm -3 .

[0050] Preferably, a low-doping layer is further included between the n-type layer 12 and the heavily doped layer 13. The low-doping layer is a Si-doped GaN layer, and the Si doping concentration is 1×10 17 ~5×10 17 cm -3 The heavily doped layer is a Si-doped GaN layer, and the Si doping concentration is 1×10 18 ~6×10 18 cm -3 .

[0051] The following is an example of the specific implementation structure of the epitaxial structure:

[0052] See also Figure 1 and Figure 2 The epitaxial structure includes, from bottom to top, a substrate 10, a buffer layer 11, an n-type layer 12, a heavily doped layer 13, a second intermediate layer 19, a current spreading layer 14, a first intermediate layer 18, an active layer 15, an electron blocking layer 16, and a p-type layer 17. The active layer 15 includes a first concentration profile 100 of In, the heavily doped layer 13 includes a second concentration profile 200 of Si, and the current spreading layer 14 includes a third concentration profile 300 of In. The minimum distance between the top of a third peak 310 in the third concentration profile 300 and the top of the first peak 110 in the first concentration profile 100 is D1, and the minimum distance between the top of the third peak 310 in the third concentration profile 300 and the top of the second peak 210 in the second concentration profile 200 is D2, and the ratio of D1 to D2 is less than 1:7.

[0053] The first concentration profile 100 includes several first peaks 110, the second concentration profile 200 includes a second peak 210, and the third concentration profile 300 includes several third peaks 310. The above-mentioned distance D1 refers to the distance between the closest third peak 310 and the first peak 110, and the above-mentioned distance D2 refers to the distance between the closest third peak 310 and the second peak 210.

[0054] By adjusting the minimum distance D1 between the peak of the third peak 310 and the peak of the first peak 110, the current spreading layer 14 is brought as close as possible to the active layer 15. This effectively guides the impact current when the epitaxial structure and the light-emitting diode using the epitaxial structure are subjected to electrostatic shock, protecting the active layer 15 from electrostatic breakdown. Furthermore, the first intermediate layer 18 between the current spreading layer 14 and the active layer 15 protects the active layer 15 from growth defects generated by the current spreading layer 14, the heavily doped layer 13, or the n-type layer 12, thereby improving the growth quality of the active layer 15. The second intermediate layer 19 between the current spreading layer 14 and the heavily doped layer 13 serves as an electron storage area and, when subjected to electrostatic shock, provides a large number of electrons to offset the external electric field, thereby reducing the risk of electrostatic breakdown in the epitaxial structure and the light-emitting diode using the epitaxial structure.

[0055] The method for preparing the epitaxial structure comprises the following steps:

[0056] S1. Growing a buffer layer 11 with a thickness of 0.5-1.5 μm on the substrate 10. The buffer layer 11 is a non-doped GaN layer and the growth temperature is 500-600° C.

[0057] S2, growing an n-type layer 12 on the buffer layer 11, wherein the n-type layer 12 is a Si-doped GaN layer, and the growth temperature is 1050-1150°C; the Si doping concentration in the n-type layer 12 is 1×10 19 ~3×10 19 cm -3 ;

[0058] S3, sequentially growing a low-doped layer and a heavily doped layer 13 on the buffer layer 11, wherein the low-doped layer is a Si-doped GaN layer, and the growth temperature is 1050-1150°C; the heavily doped layer 13 is a Si-doped GaN layer, and the growth temperature is 800-900°C; the doping concentration of Si in the low-doped layer is 1×10 17 ~5×10 17 cm -3 The doping concentration of Si in the heavily doped layer 13 is 1×10 18 ~6×10 18 cm -3 ;

[0059] S4. A second intermediate layer 19 is grown on the heavily doped layer 13. The second intermediate layer 19 is a Si-doped GaN layer, and the growth temperature is 800-900°C. The doping concentration of Si in the second intermediate layer 19 is 1×10 18 ~2×10 18 cm -3 ;

[0060] S5, grow a GaN layer with a thickness of 8-10 nm on the second intermediate layer 19, and then grow an In layer with a thickness of 1-2 nm. x Ga 1-x N layer, with the two as a super lattice unit structure, alternately grown continuously for 3 to 30 cycles, and this continuous super lattice structure is the current spreading layer 14; In x Ga 1-x The value of x in the N layer is between 0 and 0.4; the growth temperature of the current spreading layer 14 is 800-900°C;

[0061] S6. A first intermediate layer 18 is grown on the current spreading layer 14. The first intermediate layer 18 is a Si-doped GaN layer, and the growth temperature is 800-900°C. The Si doping concentration in the first intermediate layer 18 is 1.5×10 17 ~5×10 17 cm -3 ;

[0062] S7, grow a GaN barrier layer with a thickness of 4 to 12 nm on the first intermediate layer 18, and then grow an In y Ga 1-y The N potential well layer is alternately grown continuously for 6 to 20 cycles with the two forming a superlattice unit structure. This continuous superlattice structure is the active layer 15. y Ga 1-y The value of y in the N potential well layer is between 0 and 0.8; the growth temperature of the active layer 15 is 700-800°C;

[0063] S8, growing an electron blocking layer 16 on the active layer 15, wherein the electron blocking layer 16 is a Mg-doped GaN layer, and the growth temperature is 900-1000°C; the doping concentration of Mg in the electron blocking layer 16 is 1×10 18 ~3×10 18 cm -3 ;

[0064] S9, growing a p-type layer 17 on the electron blocking layer 16, wherein the p-type layer 17 is a Mg-doped GaN layer, and the growth temperature is 800-900°C; the doping concentration of Mg in the p-type layer 17 is 1×10 18 ~3×10 18 cm -3 ;

[0065] S10. Finally, annealing is performed in an inert atmosphere for 3 to 7 minutes.

[0066] According to one aspect of the present application, a light emitting diode is provided. The light emitting diode includes an epitaxial portion, and the epitaxial portion is the epitaxial structure in the above embodiment. The specific structure of the epitaxial portion will not be described in detail here.

[0067] It can be seen from the above technical solution that by adjusting the minimum distance D1 between the peak of the third peak 310 and the peak of the first peak 110, the current spreading layer 14 is made as close to the active layer 15 as possible, and when the epitaxial structure and the light-emitting diode using the epitaxial structure are subjected to electrostatic shock, the impact current can be effectively guided to protect the active layer 15 from being easily broken down by electrostatics; at the same time, the area between the current spreading layer 14 and the heavily doped layer 13 is an electron storage area, and the electron storage area has a large thickness. When subjected to electrostatic shock, the electron storage area can provide a large amount of electrons to reduce the risk of electrostatic breakdown of the epitaxial structure and the light-emitting diode using the epitaxial structure, thereby improving the anti-static ability of the epitaxial structure and the light-emitting diode using the epitaxial structure.

[0068] Furthermore, when growth defects occur during the growth of the current spreading layer 14 , the heavily doped layer 13 or the n-type layer 12 , the first intermediate layer 18 located between the current spreading layer 14 and the active layer 15 can prevent the active layer 15 from being affected by the above growth defects, thereby improving the growth quality of the active layer 15 .

[0069] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and replacements can be made without departing from the technical principles of the present application. These improvements and replacements should also be regarded as the scope of protection of the present application.

Claims

1. A light emitting diode, characterized in that: include: An n-type layer, a p-type layer, and an active layer located therebetween, wherein the active layer comprises a first concentration profile of In, and the first concentration profile comprises a plurality of first peaks; a current spreading layer, located between the n-type layer and the active layer, and comprising a third concentration profile of In, wherein the third concentration profile comprises a plurality of third peaks, and a minimum distance D1 between a peak top of the third peak and a peak top of the first peak is less than 20 nm; a first intermediate layer, located between the current spreading layer and the active layer; a heavily doped layer, located between the n-type layer and the current spreading layer, and comprising a second concentration profile of Si, the second concentration profile comprising a second peak, the minimum distance between the peak top of the third peak and the peak top of the second peak being D2, wherein D2 is greater than 150 nm; a low-doped layer, located between the n-type layer and the heavily doped layer; A second intermediate layer is included between the current spreading layer and the heavily doped layer, and a thickness of the second intermediate layer is smaller than a minimum distance D2 between a peak of the third peak shape and a peak of the second peak shape.

2. The light emitting diode according to claim 1, wherein: The concentration of the heavily doped layer is 1×10 18 ~6×10 18 cm -3 .

3. The light emitting diode according to claim 1, wherein: The thickness of the second intermediate layer is equal to or greater than 80% of D2.

4. The light emitting diode according to claim 1, wherein: The low-doped layer is a Si-doped GaN layer, and the Si doping concentration is 1×10 17 ~5×10 17 cm -3 .

5. The light emitting diode according to claim 1, wherein: The second intermediate layer is a Si-doped GaN layer, and the Si doping concentration is 1×10 18 ~2×10 18 cm -3 .

6. The light emitting diode according to claim 1, wherein: The first intermediate layer is a Si-doped GaN layer, and the Si doping concentration is 1.5×10 17 ~5×10 17 cm -3 .

7. The light emitting diode according to claim 1, wherein: The current spreading layer is a GaN layer and an In x Ga 1-x A periodic superlattice structure composed of N alternating elements, where 0≤x≤0.

4.

8. The light emitting diode according to claim 7, wherein: The number of periods of the superlattice structure in the current spreading layer is 3 to 30.

9. The light emitting diode according to claim 7, wherein: The thickness of the current spreading layer is greater than 30 nm and less than 80 nm.

10. The light emitting diode according to claim 7, characterized in that: The thickness of the GaN layer in each period of the superlattice structure is between 8 and 10 nm; the thickness of the In layer in a single period is between 8 and 10 nm. x Ga 1-x The thickness of the N layer is between 1 and 2 nm.

11. The light emitting diode according to claim 1, wherein: The active layer is a multi-layer quantum well layer composed of In y Ga 1-y A periodic superlattice structure consisting of alternating N potential well layers and GaN barrier layers; the In doping concentration in the active layer in a single period is greater than the In doping concentration in the current spreading layer in a single period.

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