Light-emitting diode epitaxial wafer, its preparation method, and LED

Abstract

The present invention discloses a light-emitting diode epitaxial wafer, a preparation method thereof, and an LED. The light-emitting diode epitaxial wafer includes a substrate, and a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer that are sequentially stacked on the substrate. The insertion layer includes a plurality of nitride triangular prisms. The nitride triangular prism includes a bottom surface and a side surface. The bottom surface is attached to the N-type GaN layer, and the side surface is a semi-polar surface. The transition layer includes a semi-polar surface GaN layer and a semi-polar surface InGaN layer that are periodically and alternately stacked. The light-emitting diode epitaxial wafer provided by the present invention can successfully convert the polar surface active layer into a semi-polar surface active layer, improve the electron leakage problem, increase the hole concentration in the quantum well layer, and improve the light-emitting efficiency.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic technologies, and particularly to a light-emitting diode epitaxial wafer, a preparation method thereof, and an LED. Background Art

[0002] At present, the preparation process of GaN-based light-emitting diodes (LEDs) grown on the (0001) plane is becoming increasingly mature, but there are still problems that need to be overcome in terms of optoelectronic conversion efficiency. The common epitaxial structure of a light-emitting diode includes a substrate, an N-type GaN layer, an active layer, and a P-type nitride layer. Since the GaN crystal on the (0001) plane has polarity, it not only causes the energy band of the active layer to bend, reducing the overlap of the electron wave functions of electrons and holes, but also makes the electron wave function closer to the P-type nitride layer side, resulting in easier electron leakage, which greatly affects the performance of the light-emitting device. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a light-emitting diode epitaxial wafer, which can successfully convert the active layer of the polar plane into the active layer of the semi-polar plane, improve the electron leakage problem, and at the same time increase the hole concentration in the quantum well layer and improve the light-emitting efficiency.

[0004] The technical problem to be solved by the present invention is also to provide a preparation method of a light-emitting diode epitaxial wafer, which has a simple process and can stably produce a light-emitting diode epitaxial wafer with good light-emitting efficiency.

[0005] To solve the above technical problems, the present invention provides a light-emitting diode epitaxial wafer, including a substrate and a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer sequentially stacked on the substrate;

[0006] The insertion layer includes a plurality of nitride triangular prisms. The nitride triangular prism includes a bottom surface and a side surface. The bottom surface is attached to the N-type GaN layer, and the side surface is a semi-polar plane.

[0007] In one embodiment, the height of the nitride triangular prism protruding upward from the bottom surface is 100 nm to 500 nm.

[0008] In one embodiment, the side surface includes a first side surface and a second side surface,

[0009] The first side surface is a (10-13) semi-polar plane or a (11-22) semi-polar plane;

[0010] The second side surface is a (10-13) semi-polar plane or a (11-22) semi-polar plane.

[0011] In one embodiment, the transition layer includes periodically alternating stacked semi-polar GaN layers and semi-polar InGaN layers.

[0012] In one embodiment, a single semi-polar GaN layer and a single semi-polar InGaN layer form a periodic layer, and the transition layer includes 3 to 6 of such periodic layers;

[0013] The thickness of the periodic layer is 5 nm to 30 nm.

[0014] In one embodiment, the semi-polar GaN layer has Si doping, and the Si doping concentration is 1×10 18 atoms / cm 3 ~1×10 19 atoms / cm 3 .

[0015] In one embodiment, the active layer is periodically alternating stacked semi-polar quantum barrier layers and semi-polar quantum well layers;

[0016] The number of periods of the periodic alternating stack is 3 to 6.

[0017] In one embodiment, the semi-polar quantum barrier layer is a semi-polar Al x Ga 1-x N quantum barrier layer, and the semi-polar quantum well layer is a semi-polar In y Ga 1-y N quantum well layer, where 0 ≤ x ≤ 0.1 and 0.1 ≤ y ≤ 0.3;

[0018] The thickness of the semi-polar quantum barrier layer is 8 nm to 12 nm;

[0019] The thickness of the semi-polar quantum well layer is 2 nm to 5 nm.

[0020] To solve the above problems, the present invention provides a method for preparing a light-emitting diode epitaxial wafer, including the following steps:

[0021] S1. Prepare a substrate;

[0022] S2. Deposit a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer on the substrate in sequence;

[0023] The insertion layer includes a plurality of nitride triangular prisms, the nitride triangular prism includes a bottom surface and a side surface, the bottom surface is attached to the N-type GaN layer, and the side surface is a semi-polar surface.

[0024] Correspondingly, the present invention also provides an LED, and the LED includes the above-mentioned light-emitting diode epitaxial wafer.

[0025] Implementing the present invention has the following beneficial effects:

[0026] The light-emitting diode epitaxial wafer provided by the present invention has an insertion layer with a specific structure. The insertion layer includes a plurality of nitride triangular prisms. The nitride triangular prism includes a bottom surface and side surfaces. The bottom surface is attached to the N-type GaN layer, and the side surfaces are semi-polar surfaces.

[0027] Through the structures of the specific insertion layer, transition layer, and active layer of the present invention, the polar-plane active layer is successfully converted into a semi-polar-plane active layer, and has relatively high crystal quality, weakening the polarization effects of the active layer and the electron blocking layer, increasing the effective barrier height of the quantum barrier layer and the electron blocking layer, while reducing the hole injection barrier, improving the electron leakage problem, increasing the hole concentration in the quantum well, and improving the light-emitting efficiency. Description of the Drawings

[0028] Figure 1 is a schematic structural diagram of the light-emitting diode epitaxial wafer provided by the present invention;

[0029] Figure 2 is a flowchart of the manufacturing method of the light-emitting diode epitaxial wafer provided by the present invention;

[0030] Figure 3 is a flowchart of step S2 of the manufacturing method of the light-emitting diode epitaxial wafer provided by the present invention. Detailed Embodiments

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below.

[0032] Unless otherwise specified or there are contradictions, the terms or phrases used herein have the following meanings:

[0033] In the present invention, "preferred" only describes the embodiments or examples with better effects, and it should be understood that it does not constitute a limitation on the protection scope of the present invention.

[0034] In the present invention, for the technical features described in an open-ended manner, it includes the closed technical solutions composed of the listed features, as well as the open technical solutions including the listed features.

[0035] In the present invention, regarding the numerical range, unless otherwise specified, it includes both endpoints of the numerical range.

[0036] To solve the above problems, the present invention provides a light-emitting diode epitaxial wafer, as Figure 1As shown in the figure, it includes a substrate 1, a buffer layer 2, an intrinsic GaN layer 3, an N-type GaN layer 4, an insertion layer 5, a transition layer 6, an active layer 7, and a P-type nitride layer 8 that are sequentially stacked on the substrate 1;

[0037] On the insertion layer 5, there are several nitride triangular prisms. The nitride triangular prism includes a bottom surface and side surfaces. The bottom surface is in contact with the N-type GaN layer, and the side surfaces are semi-polar surfaces.

[0038] In the present invention, through the structures of the specific insertion layer 5, transition layer 6, and active layer 7, the polar-plane active layer is successfully converted into a semi-polar-plane active layer, and it has relatively high crystal quality, weakens the polarization effect of the active layer and the electron blocking layer, increases the effective barrier height of the quantum barrier layer and the electron blocking layer, and at the same time reduces the hole injection barrier. While improving the electron leakage problem, it increases the hole concentration in the quantum well and improves the light emission efficiency. The specific structures of the insertion layer, transition layer, and active layer are described in detail below.

[0039] First, the introduction of the insertion layer 5 provides a basis for successfully converting the polar-plane active layer into a semi-polar-plane active layer in the subsequent process. In one embodiment, the height of the nitride triangular prism of the insertion layer 5 protruding upward from the bottom surface is 100 nm to 500 nm; exemplarily, the height of the nitride triangular prism protruding upward from the bottom surface is 200 nm, 300 nm, 400 nm, but not limited thereto;

[0040] In one embodiment, the side surfaces include a first side surface and a second side surface. The first side surface is a (10-13) semi-polar surface or a (11-22) semi-polar surface; the second side surface is a (10-13) semi-polar surface or a (11-22) semi-polar surface. When the side surface of the nitride triangular prism is a (10-13) semi-polar surface, the grown epitaxial thin film is beneficial to preventing the leakage of hole states; when the side surface of the nitride triangular prism is a (11-22) semi-polar surface, the overall crystal quality of the grown epitaxial thin film is higher, which can improve the performance of the device. Among them, when the included angle between the side surface and the bottom surface is 30° to 34°, the side surface is a (10-13) semi-polar surface; when the included angle between the side surface and the bottom surface is 56° to 60°, the side surface is a (11-22) semi-polar surface. The first side surface and the second side surface are both (10-13) semi-polar surfaces or (11-22) semi-polar surfaces, or the first side surface and the second side surface are respectively a (10-13) semi-polar surface and a (11-22) semi-polar surface. The present invention does not make a limitation on this.

[0041] Then, a transition layer 6 is introduced on the insertion layer 5. In one embodiment, the transition layer 6 includes periodically alternating stacked semi-polar GaN layers and semi-polar InGaN layers; a single semi-polar GaN layer and a single semi-polar InGaN layer form a periodic layer, and the transition layer 6 includes 3 to 6 such periodic layers; the thickness of the periodic layer is 5 nm to 30 nm; the semi-polar GaN layer has Si doping, and the Si doping concentration is 1×10 18 atoms / cm 3 ~1×10 19 atoms / cm 3 . The semi-polar InGaN layer in the transition layer has a lower potential well than the semi-polar GaN layer, which can slow down the electron migration rate, prevent electrons from leaking to the P-type nitride layer, increase the electron concentration in the active layer, and improve the light-emitting efficiency. In addition, the semi-polar GaN layer has a higher crystal quality than the semi-polar InGaN layer. The introduction of SI doping improves the current spreading ability of the semi-polar GaN layer. The superlattice structure formed by the periodic alternating growth of the two can, on the one hand, block the extension of dislocations and improve the crystal quality of itself and the subsequent active layer, and on the other hand, can also improve the anti-static ability during this period.

[0042] Finally, the active layer 7 is stacked on the transition layer 6. In one embodiment, the active layer 7 is a periodically alternating stacked semi-polar quantum barrier layer and semi-polar quantum well layer; the number of periodically alternating stacks is 3 to 6. Preferably, the semi-polar quantum barrier layer is a semi-polar Al x Ga 1-x N quantum barrier layer, and the semi-polar quantum well layer is a semi-polar In y Ga 1-y N quantum well layer, where 0≤x≤0.1 and 0.1≤y≤0.3; the thickness of the semi-polar quantum barrier layer is 8 nm to 12 nm; the thickness of the semi-polar quantum well layer is 2 nm to 5 nm.

[0043] It should be noted that along the N-type to P-type direction, the energy band of the quantum well of the polar plane is severely bent upward, resulting in the electron wave function approaching the P-type side direction and the hole wave function approaching the N-type side. This leads to easy electron leakage while reducing the overlap of the electron and hole wave functions, affecting the light-emitting efficiency. By introducing the insertion layer in the present invention, it is possible to deposit a semi-polar quantum well layer, so that the energy band of the quantum well layer is inverted, the electron wave function is relatively closer to the N-type side, and the hole wave function is relatively closer to the P-type side. This greatly improves the problem of electron leakage, increases the overlap of the electron and hole wave functions, and improves the light-emitting efficiency and device reliability.

[0044] Furthermore, along the N-type to P-type direction, with the alternating growth of the quantum well layer and the quantum barrier layer, the polarization electric field of the quantum barrier on the polar surface gradually increases. In particular, there is a strong polarization electric field at the interface between the last polar quantum barrier and the P-type electron blocking layer, resulting in severe band bending and a reduction in the effective blocking barrier for electrons. By introducing the insertion layer in the present invention, it is possible to deposit a semi-polar quantum barrier layer, thereby weakening the polarization electric field, facilitating a reduction in the degree of band bending, increasing the effective barrier height while reducing the hole injection barrier, improving electron leakage, and increasing the hole concentration in the semi-polar quantum well layer, thus improving the light emission efficiency.

[0045] In summary, through the specific structures of the insertion layer, the transition layer, and the active layer in the present invention, the polar active layer is successfully converted into a semi-polar active layer, which has a relatively high crystal quality, weakens the polarization effect of the active layer and the electron blocking layer, increases the effective barrier height of the quantum barrier layer and the electron blocking layer, while reducing the hole injection barrier, improves the electron leakage problem, increases the hole concentration in the quantum well, and improves the light emission efficiency.

[0046] Correspondingly, the present invention provides a method for preparing a light-emitting diode epitaxial wafer, as Figure 2 shown, comprising the following steps:

[0047] S1. Prepare a substrate 1;

[0048] In one embodiment, the substrate can be any one of a sapphire substrate, a silicon carbide substrate, and a gallium nitride substrate. Preferably, a sapphire substrate is used as the growth substrate for the epitaxial layer.

[0049] S2. Sequentially deposit a buffer layer 2, an intrinsic GaN layer 3, an N-type GaN layer 4, an insertion layer 5, a transition layer 6, an active layer 7, and a P-type nitride layer 8 on the substrate 1.

[0050] In one embodiment, as Figure 3 shown, step S2 comprises the following steps:

[0051] S21. Deposit a buffer layer 2 on the substrate 1.

[0052] Preferably, the buffer layer is selected from any one or a combination of an AlN buffer layer, an AlGaN buffer layer, and a GaN buffer layer. Preferably, the buffer layer is an AlGaN buffer layer and a GaN buffer deposited sequentially. The deposition process is: control the temperature of the reaction chamber at 750°C to 820°C, the pressure at 100 torr to 200 torr, introduce an N source, a gallium source, and an aluminum source to grow an AlGaN buffer layer, and control the thickness of the deposited AlGaN buffer layer to be 0.5 nm to 3 nm; then stop introducing the aluminum source and control the thickness of the deposited GaN buffer layer to be 5 nm to 25 nm.

[0053] S22. Deposit an intrinsic GaN layer 3 on the buffer layer 2.

[0054] Preferably, while controlling the temperature of the reaction chamber at 1050 °C to 1200 °C and the pressure at 150 torr to 200 torr, introduce a nitrogen source and a gallium source to grow an intrinsic GaN layer, and control the thickness of the deposited intrinsic GaN layer to be 1 μm to 1.4 μm.

[0055] S23. Deposit an N-type GaN layer 4 on the intrinsic GaN layer 3.

[0056] Preferably, control the temperature of the reaction chamber to 1040 °C to 1160 °C, introduce a nitrogen source, a gallium source, and an N-type dopant, and the doping concentration of Si is 1×10 18 atoms / cm 3 ~1×10 19 atoms / cm 3 , and control the thickness of the deposited N-type GaN layer to be 1.1 μm to 1.8 μm.

[0057] S24. Deposit an insertion layer 5 on the N-type GaN layer 4.

[0058] As described above, the insertion layer includes a plurality of nitride triangular prisms. The nitride triangular prism includes a bottom surface and side surfaces. The bottom surface is attached to the N-type GaN layer, and the side surfaces are semi-polar surfaces.

[0059] Preferably, the preparation process of the insertion layer is as follows: first, set the temperature of the reaction chamber at 1040 °C to 1160 °C, introduce a nitrogen source and a gallium source, and deposit a GaN base layer on the N-type gallium nitride layer; then perform photolithography and wet etching on the GaN base layer to prepare nitride triangular prisms with semi-polar side surfaces. The specific structure of the nitride triangular prism is as described above and will not be elaborated here.

[0060] S25. Deposit a transition layer 6 on the insertion layer 5.

[0061] Preferably, the transition layer includes periodically alternating stacked semi-polar GaN layers and semi-polar InGaN layers. The preparation process of the transition layer is as follows: first, control the temperature of the reaction chamber to 800 °C to 900 °C, control the pressure at 150 torr to 250 torr, introduce a nitrogen source and a gallium source, deposit a semi-polar GaN layer, and then introduce an indium source to deposit a semi-polar InGaN layer, and obtain the transition layer by alternating stacking.

[0062] It should be noted that the growth rate of the semi-polar plane is relatively low, and a larger flow rate often needs to be introduced to ensure a sufficiently high growth rate. Preferably, the flow rate of the nitrogen source is 100 L to 150 L, the flow rate of the gallium source is 800 sccm to 1500 sccm, and the flow rate of the indium source is 1100 sccm to 1600 sccm. This can ensure the deposition quality of the transition layer.

[0063] S26. Deposit the active layer 7 on the transition layer 6.

[0064] Preferably, the active layer is a periodically alternating stack of semi-polar plane quantum barrier layers and semi-polar plane quantum well layers. Further, the growth temperature of the semi-polar plane quantum barrier layer is 860 °C to 900 °C; the growth temperature of the semi-polar plane quantum well layer is 770 °C to 800 °C;

[0065] S27. Deposit the P-type nitride layer 8 on the active layer 7.

[0066] Preferably, the P-type nitride layer 8 includes an electron blocking layer 81, a planarizing layer 82, and a P-type GaN layer 83 deposited in sequence.

[0067] Further, the electron blocking layer is an AlInGaN electron blocking layer. The specific deposition process is: control the reaction chamber temperature to 950 °C to 980 °C, and control the thickness of the deposited AlInGaN electron blocking layer to be 15 nm to 25 nm.

[0068] The planarizing layer is a P-type undoped GaN planarizing layer. The specific deposition process is: the reaction chamber temperature is 980 °C to 1050 °C, introduce raw materials, and introduce a large amount of H 2 , and complete the deposition. Control the thickness of the deposited P-type undoped GaN planarizing layer to be 15 nm to 20 nm, so that the P-type undoped GaN planarizing layer can fill the V-shaped pits on the surface of the epitaxial layer.

[0069] The specific deposition process of the P-type GaN layer is: the reaction chamber temperature is 930 °C to 1000 °C, introduce raw materials, and introduce a large amount of H 2 , and complete the deposition. The thickness of the P-type GaN layer is 5 nm to 15 nm, and the doping concentration of Mg is 1×10 18 atoms / cm 3 -1×10 20 atoms / cm 3 .

[0070] Correspondingly, the present invention also provides an LED, and the LED includes the above-mentioned light-emitting diode epitaxial wafer. The photoelectric efficiency of the LED is effectively improved, and other electrical properties are good.

[0071] The present invention will be further described below with specific embodiments:

[0072] Embodiment 1

[0073] This embodiment provides a light-emitting diode epitaxial wafer, including a substrate and a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer that are sequentially stacked on the substrate;

[0074] The insertion layer includes a plurality of nitride triangular prisms. The nitride triangular prism includes a bottom surface and side surfaces. The bottom surface is attached to the N-type GaN layer, and the side surfaces are semi-polar surfaces.

[0075] The height of the nitride triangular prism protruding upward from the bottom surface is 150 nm. The side surfaces include a first side surface and a second side surface. The first side surface is a (10-13) semi-polar surface, and the second side surface is a (11-22) semi-polar surface.

[0076] The transition layer includes 5 cycles of alternately stacked semi-polar GaN layers and semi-polar InGaN layers.

[0077] The active layer is 5 cycles of alternately stacked semi-polar Al x Ga 1-x N quantum barrier layers and semi-polar In y Ga 1-y N quantum well layers, where x is 0.1 and y is 0.3.

[0078] Embodiment 2

[0079] This embodiment provides a light-emitting diode epitaxial wafer, which is different from Embodiment 1 in that: both the first side surface and the second side surface are (11-22) semi-polar surfaces. The rest are the same as Embodiment 1.

[0080] Embodiment 3

[0081] This embodiment provides a light-emitting diode epitaxial wafer, which is different from Embodiment 1 in that: both the first side surface and the second side surface are (10-13) semi-polar surfaces. The rest are the same as Embodiment 1.

[0082] Comparative Example 1

[0083] This comparative example is different from Embodiment 1 in that there is no insertion layer and transition layer, and the active layer is a periodically alternately stacked polar quantum barrier layer and polar quantum well layer (original traditional structure).

[0084] Comparative Example 2

[0085] This comparative example is different from Embodiment 1 in that there is no transition layer, and the rest are the same as Embodiment 1.

[0086] Comparative Example 3

[0087] The difference between this comparative example and Example 1 is that the transition layer is only a semi-polar GaN layer, and the rest are the same as those in Example 1.

[0088] Comparative Example 4

[0089] The difference between this comparative example and Example 1 is that the transition layer is only a semi-polar InGaN layer, and the rest are the same as those in Example 1.

[0090] The light-emitting diode epitaxial wafers prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were used to prepare 10×24 mil chips under the same chip process conditions. 300 LED chips were respectively extracted, and the optoelectronic properties of the chips were tested under 120 mA / 60 mA currents. The luminous efficiencies of Examples 1 to 3 and Comparative Examples 1 to 4 were calculated. The specific test results are shown in Table 1.

[0091] Table 1 Performance test results of LEDs prepared in Examples 1 to 3 and Comparative Examples 1 to 4

[0092]

[0093]

[0094] It can be seen from the above results that through the structures of the specific insertion layer, transition layer and active layer of the present invention, the polar active layer is successfully converted into a semi-polar active layer, and has relatively high crystal quality, weakens the polarization effect of the active layer and the electron blocking layer, increases the effective barrier height of the quantum barrier layer and the electron blocking layer, and at the same time reduces the injection barrier of holes, improves the electron leakage problem, increases the hole concentration in the quantum well, and improves the luminous efficiency.

[0095] The above is the preferred implementation manner of the invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A light-emitting diode epitaxial wafer, characterized in that, it comprises a substrate and a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer that are sequentially stacked on the substrate; there are several nitride triangular prisms on the insertion layer, the nitride triangular prism comprises a bottom surface and side surfaces, the bottom surface is attached to the N-type GaN layer, and the side surfaces are semi-polar planes; the transition layer comprises periodically and alternately stacked semi-polar plane GaN layers and semi-polar plane InGaN layers.

2. The light-emitting diode epitaxial wafer according to claim 1, characterized in that, the height of the nitride triangular prism protruding upward from the bottom surface is 100 nm to 500 nm.

3. The light-emitting diode epitaxial wafer according to claim 1, characterized in that, the side surfaces comprise a first side surface and a second side surface, the first side surface is a (10-13) semi-polar plane or a (11-22) semi-polar plane; the second side surface is a (10-13) semi-polar plane or a (11-22) semi-polar plane.

4. The light-emitting diode epitaxial wafer according to claim 1, characterized in that, a single semi-polar plane GaN layer and a single semi-polar plane InGaN layer form a periodic layer, and the transition layer comprises 3 to 6 of the periodic layers.

5. The light-emitting diode epitaxial wafer according to claim 4, characterized in that, the thickness of the periodic layer is 5 nm to 30 nm.

6. The light-emitting diode epitaxial wafer according to claim 1, characterized in that, The semi-polar plane GaN layer has Si doping, and the Si doping concentration is 1×10 18 atoms / cm 3 ~1×10 19 atoms / cm 3 。 7. The light-emitting diode epitaxial wafer according to claim 1, characterized in that, the active layer is a periodically and alternately stacked semi-polar plane quantum barrier layer and semi-polar plane quantum well layer; the number of periods of the periodic alternation and stacking is 3 to 6.

8. The light-emitting diode epitaxial wafer according to claim 7, characterized in that, The semi-polar surface quantum barrier layer is a semi-polar surface Al x Ga 1-x N quantum barrier layer, and the semi-polar surface quantum well layer is a semi-polar surface In y Ga 1-y N quantum well layer, where 0 ≤ x ≤ 0.1 and 0.1 ≤ y ≤ 0.3; the thickness of the semi-polar plane quantum barrier layer is 8 nm to 12 nm; the thickness of the semi-polar plane quantum well layer is 2 nm to 5 nm.

9. A method for preparing a light-emitting diode epitaxial wafer according to any one of claims 1 to 8, characterized in that, it comprises the following steps: S1. Prepare a substrate; S2. Deposit a buffer layer, an intrinsic GaN layer, an N-type GaN layer, an insertion layer, a transition layer, an active layer, and a P-type nitride layer on the substrate in sequence; there are several nitride triangular prisms on the insertion layer, the nitride triangular prism comprises a bottom surface and side surfaces, the bottom surface is attached to the N-type GaN layer, and the side surfaces are semi-polar planes.

10. An LED, characterized in that, the LED comprises a light-emitting diode epitaxial wafer according to any one of claims 1 to 8.

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