Light emitting diode epitaxial wafer and preparation method thereof, LED
By employing a multi-quantum-well layer with a specific structure in the epitaxial wafer of a light-emitting diode (LED), including a BN layer, an AlInGaN layer, and a Si-doped InN layer, the problems of lattice mismatch and polarization effect of the InGaN quantum well layer/AlGaN quantum barrier layer are solved, thereby improving the luminous efficiency of the LED.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGXI ZHAO CHI SEMICON CO LTD
- Filing Date
- 2023-12-13
- Publication Date
- 2026-06-16
AI Technical Summary
In existing technologies, InGaN quantum well layers/AlGaN quantum barrier layers suffer from lattice mismatch, high dislocation density, and large polarization effects, resulting in low luminous efficiency.
A multi-quantum well layer with a specific structure, including alternating stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers, can reduce lattice mismatch and polarization effects and improve crystal quality and radiative recombination efficiency by varying the composition and controlling the doping.
The defect density of the quantum well layer was reduced, the crystal quality and radiative recombination efficiency of the quantum well layer were improved, and the luminous efficiency of the light-emitting diode was enhanced.
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Figure CN117691014B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optoelectronic technology, and in particular to a light-emitting diode epitaxial wafer and its preparation method, and LEDs. Background Technology
[0002] InGaN, as a third-generation semiconductor material, has been widely used in the fabrication of devices such as blue LEDs due to its wide tunable bandgap and the ability to cover the entire visible light spectrum with corresponding emission wavelengths.
[0003] Currently, commercially available high-efficiency GaN-based blue-green light-emitting diodes typically use InGaN quantum well layers / AlGaN quantum barrier layers as the active region. Therefore, high-quality InGaN quantum well layers / AlGaN quantum barrier layers are crucial for achieving high-efficiency, high-brightness LEDs. However, InGaN quantum well layers / AlGaN quantum barrier layers have the following problems:
[0004] First, there is a large lattice mismatch and thermal mismatch between GaN and sapphire, resulting in a dislocation density of over 10-1 for GaN films grown on sapphire substrates. 8 cm -2 Up to 10 10 cm -2 First, the large magnitude of the luminescence results in poor quantum well crystal quality and low radiative recombination efficiency. Second, lattice mismatch between the InGaN quantum well layer and the AlGaN quantum barrier layer causes stress, which leads to point defects and impurities, thus reducing luminous efficiency. Third, the significant polarization effect between the InGaN quantum well layer and the AlGaN quantum barrier layer causes band tilting, reducing the coupling between electron and hole wave functions in the quantum well and lowering the quantum efficiency within the LED. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a light-emitting diode epitaxial wafer that reduces the defect density of the quantum well layer, improves the crystal quality of the quantum well layer, reduces the polarization effect of the quantum well layer, and improves the radiative recombination efficiency of multiple quantum well layers.
[0006] The technical problem to be solved by the present invention is to provide a method for preparing an epitaxial wafer of a light-emitting diode, which has a simple process and can stably produce an epitaxial wafer of a light-emitting diode with good luminous efficiency.
[0007] To solve the above-mentioned technical problems, the present invention provides a light-emitting diode epitaxial wafer, including a substrate, wherein a buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially disposed on the substrate.
[0008] The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
[0009] In one embodiment, the thickness of the BN layer is 5 nm to 50 nm.
[0010] In one embodiment, the thickness of the AlInGaN layer is 0.1 nm to 10 nm;
[0011] The Al composition of the AlInGaN layer is 0.01 to 0.1.
[0012] The In composition of the AlInGaN layer is 0.01 to 0.5.
[0013] In one embodiment, the Al content of the AlInGaN layer gradually decreases along the growth direction, while the In content gradually increases along the growth direction.
[0014] In one embodiment, the thickness of the Si-doped InN layer is 0.1 nm to 5 nm;
[0015] The Si doping concentration of the Si-doped InN layer is 1×10⁻⁶. 17 atoms / cm 3 ~1×10 18 atoms / cm 3 .
[0016] In one embodiment, the thickness of the InGaN layer is 0.5 nm to 10 nm;
[0017] The In composition of the InGaN layer is 0.01 to 0.5.
[0018] In one embodiment, the multi-quantum-well layer comprises 1 to 20 periodically alternating composite quantum-well layers and quantum barrier layers.
[0019] In one embodiment, the quantum barrier layer is an AlGaN layer, and the Al composition of the AlGaN layer is 0.01 to 0.5.
[0020] To address the above problems, the present invention also provides a method for fabricating a light-emitting diode epitaxial wafer, comprising the following steps:
[0021] S1. Prepare the substrate;
[0022] S2. A buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially deposited on the substrate.
[0023] The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
[0024] Accordingly, the present invention also provides an LED, which includes the above-described light-emitting diode epitaxial wafer.
[0025] Implementing this invention has the following beneficial effects:
[0026] The light-emitting diode epitaxial wafer provided by the present invention has a multi-quantum well layer with a specific structure. The multi-quantum well layer includes multiple alternately stacked composite quantum well layers and quantum barrier layers. The composite quantum well layer includes a BN layer, an AlInGaN layer, a Si-doped InN layer, and an InGaN layer stacked sequentially.
[0027] The BN layer causes dislocation torsion, preventing dislocations from extending into the epitaxial layer and improving the crystal quality of the epitaxial layer. The AlInGaN layer, through its compositional variation, reduces the lattice mismatch between the InGaN quantum well layer and the AlGaN barrier layer, reducing stress-induced defects, improving the crystal quality of the quantum well layer, and lowering its nonradiative recombination efficiency. The Si-doped InN layer modulates the piezoelectric field of the quantum well layer through Si doping, reducing the polarization effect. Furthermore, the InN layer promotes electron and hole trapping and recombination for luminescence during electron and hole injection. The thickness of the InGaN layer is smaller than the de Broglie wavelength of electrons, resulting in discrete quantized energy levels for electrons and holes, exhibiting a significant quantum confinement effect. The In-rich regions of the InGaN layer generate potential valleys, which become potential wells for charge carriers. During electron and hole injection, these wells easily trap and recombine for luminescence, greatly reducing the probability of nonradiative recombination due to dislocation trapping and improving the luminous efficiency of the light-emitting diode.
[0028] In summary, by growing multi-period composite quantum well layers and quantum barrier layers, the quantum confinement effect is enhanced, and electrons and holes are localized in multiple quantum wells, thereby increasing the overlap of electron and hole wave functions and thus improving the radiative recombination rate. Ultimately, this reduces the defect density of the quantum well layer, improves the crystal quality of the quantum well layer, reduces the polarization effect of the quantum well layer, and improves the radiative recombination efficiency of the multi-quantum well layer. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of the structure of the light-emitting diode epitaxial wafer provided by the present invention;
[0030] Figure 2 A flowchart illustrating the method for fabricating a light-emitting diode epitaxial wafer provided by the present invention;
[0031] Figure 3The flowchart shows step S2 of the method for preparing a light-emitting diode epitaxial wafer provided by the present invention. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below.
[0033] Unless otherwise stated or in case of contradiction, the terms or phrases used herein shall have the following meanings:
[0034] In this invention, "preferred" is merely a description of a more effective implementation method or embodiment, and should be understood as not constituting a limitation on the scope of protection of this invention.
[0035] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.
[0036] In this invention, numerical ranges are involved, and unless otherwise specified, they include the two endpoints of the numerical range.
[0037] To address the above problems, the present invention provides a light-emitting diode epitaxial wafer, such as... Figure 1 As shown, the substrate includes a substrate 100, on which a buffer layer 200, an undoped GaN layer 300, an N-type GaN layer 400, a multiple quantum well layer 500, an electron blocking layer 600, and a P-type GaN layer 700 are sequentially disposed.
[0038] The multi-quantum well layer 500 includes multiple alternating layers of composite quantum well layers 510 and quantum barrier layers 520. The composite quantum well layer 510 includes a BN layer 511, an AlInGaN layer 512, a Si-doped InN layer 513, and an InGaN layer 514 stacked sequentially.
[0039] The specific structure of the multi-quantum-well layer 500 is as follows:
[0040] In one embodiment, the thickness of the BN layer 511 is 5nm to 50nm; exemplary thicknesses of the BN layer 511 are 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, and 45nm, but are not limited thereto. The BN layer 511 causes dislocations to twist, preventing dislocations from extending into the epitaxial layer and improving the crystal quality of the epitaxial layer.
[0041] In one embodiment, the thickness of the AlInGaN layer 512 is 0.1 nm to 10 nm. Exemplary thicknesses of the AlInGaN layer 512 are 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, and 9 nm, but are not limited thereto. In one embodiment, the Al composition of the AlInGaN layer 512 is 0.01 to 0.1, and the In composition is 0.01 to 0.5. Preferably, the Al composition of the AlInGaN layer 512 is 0.02 to 0.09, and the In composition is 0.1 to 0.4. More preferably, the Al composition of the AlInGaN layer 512 gradually decreases along the growth direction, and the In composition gradually increases along the growth direction. Through its compositional variation, the AlInGaN layer 512 reduces the lattice mismatch between the InGaN quantum well layer and the AlGaN barrier layer, reduces defects caused by stress, improves the crystal quality of the quantum well layer, and reduces the non-radiative recombination efficiency of the quantum well layer.
[0042] In one embodiment, the thickness of the Si-doped InN layer 513 is 0.1 nm to 5 nm; exemplary thicknesses of the Si-doped InN layer 513 are 1 nm, 1.5 nm, 2 nm, 2.5 nm, 3 nm, 3.5 nm, 4 nm, and 4.5 nm, but are not limited thereto. In one embodiment, the Si doping concentration of the Si-doped InN layer 513 is 1 × 10⁻⁶. 17 atoms / cm 3 ~1×10 18 atoms / cm 3 Preferably, the Si doping concentration of the Si-doped InN layer 513 is 2 × 10⁻⁶. 17 atoms / cm 3 ~9×10 17 atoms / cm 3 The Si-doped InN layer modulates the piezoelectric field of the quantum well layer through Si doping, reducing the polarization effect of the quantum well layer. In addition, the InN layer promotes electron and hole capture and recombination for luminescence during electron and hole injection.
[0043] In one embodiment, the thickness of the InGaN layer 514 is 0.5 nm to 10 nm; exemplary thicknesses of the InGaN layer 514 are 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, and 9 nm, but are not limited thereto. In one embodiment, the In composition of the InGaN layer 514 is 0.01 to 0.5; preferably, the In composition of the InGaN layer 514 is 0.1 to 0.4. The thickness of the InGaN layer 514 is smaller than the de Broglie wavelength of electrons, and the energy levels of electrons and holes are discrete quantized energy levels, exhibiting a significant quantum confinement effect. The In-rich regions of the InGaN layer generate potential valleys, and the In-rich regions become potential wells for charge carriers. When electrons and holes are injected, they are easily captured by these potential wells and recombine to emit light, greatly reducing the probability of nonradiative recombination due to dislocation trapping and improving the luminous efficiency of the light-emitting diode.
[0044] In one embodiment, the multi-quantum-well layer 500 includes a composite quantum well layer 510 and a quantum barrier layer 520 stacked alternately with 1 to 20 periods; exemplary periods are 2, 4, 6, 8, 10, 12, 14, 16, and 18, but are not limited thereto. In one embodiment, the quantum barrier layer 520 is an AlGaN layer, and the Al composition of the AlGaN layer is 0.01 to 0.5. A suitable quantum barrier layer can both reduce electron overflow into the p-type layer leading to nonradiative recombination and improve the recombination efficiency of electrons and holes in the quantum well.
[0045] In summary, by growing multi-period composite quantum well layers and quantum barrier layers, the quantum confinement effect is enhanced, and electrons and holes are localized in multiple quantum wells, thereby increasing the overlap of electron and hole wave functions and thus improving the radiative recombination rate. Ultimately, this reduces the defect density of the quantum well layer, improves the crystal quality of the quantum well layer, reduces the polarization effect of the quantum well layer, and improves the radiative recombination efficiency of the multi-quantum well layer.
[0046] Accordingly, the present invention provides a method for fabricating a light-emitting diode epitaxial wafer, such as... Figure 2 As shown, it includes the following steps:
[0047] S1. Prepare substrate 100;
[0048] The substrate can be selected from one of the following: sapphire substrate, SiO2 sapphire composite substrate, silicon substrate, silicon carbide substrate, gallium nitride substrate, and zinc oxide substrate.
[0049] Preferably, the substrate is a sapphire substrate. Sapphire is currently the most commonly used GaN-based LED substrate material. Sapphire substrates have mature manufacturing processes, low prices, are easy to clean and process, and have good stability at high temperatures.
[0050] S2. A buffer layer 200, an undoped GaN layer 300, an N-type GaN layer 400, a multiple quantum well layer 500, an electron blocking layer 600, and a P-type GaN layer 700 are sequentially deposited on the substrate 100.
[0051] like Figure 3 As shown, step S2 specifically includes the following steps:
[0052] S21. Deposit a buffer layer 200 on the substrate 100.
[0053] In one embodiment, an AlN buffer layer with a thickness of 10 nm to 20 nm is deposited in PVD. The AlN buffer layer provides nucleation centers with the same orientation as the substrate, releasing the stress caused by the lattice mismatch between GaN and the substrate, as well as the thermal stress caused by the mismatch in the coefficient of thermal expansion. Further growth provides a flat nucleation surface, reducing the contact angle of nucleation growth and enabling the island-shaped GaN grains to connect into a surface within a smaller thickness, thus transforming into two-dimensional epitaxial growth.
[0054] Preferably, the sapphire substrate with the AlN buffer layer deposited is transferred into MOCVD and pretreated in H2 atmosphere for 1 min to 10 min at a temperature of 1000℃ to 1200℃. Then, the sapphire substrate is nitrided to improve the crystal quality of the AlN buffer layer and effectively improve the crystal quality of the subsequently deposited GaN epitaxial layer.
[0055] S22. Deposit an undoped GaN layer 300 on the buffer layer 200.
[0056] In one embodiment, the temperature of the reaction chamber is controlled at 1050℃~1200℃, the pressure is controlled at 100 torr~600 torr, and an N source and a Ga source are introduced to grow an undoped GaN layer with a thickness of 1μm~5μm.
[0057] S23. Deposit an N-type GaN layer 400 on the undoped GaN layer 300.
[0058] In one embodiment, the temperature of the reaction chamber is controlled at 1050°C to 1200°C, the pressure is controlled at 100 torr to 600 torr, and an N source, a Ga source, and a Si source are introduced to grow the N-type GaN layer.
[0059] S24. Deposit a multi-quantum-well layer 500 on the N-type GaN layer 400.
[0060] The multi-quantum well layer 500 includes multiple alternating layers of composite quantum well layers 510 and quantum barrier layers 520. The composite quantum well layer 510 includes a BN layer 511, an AlInGaN layer 512, a Si-doped InN layer 513, and an InGaN layer 514 stacked sequentially.
[0061] In one embodiment, the BN layer 511 is prepared by the following method:
[0062] The temperature of the reaction chamber is controlled at 900℃~1100℃, the pressure is controlled at 50torr~300torr, and a mixed atmosphere of N2 and NH3 is introduced to grow a BN layer.
[0063] In one embodiment, the AlInGaN layer 512 is prepared by the following method:
[0064] The temperature of the reaction chamber is controlled at 700℃~900℃, the pressure is controlled at 50torr~300torr, and a mixed atmosphere of N2, H2 and NH3 is introduced to grow an AlInGaN layer.
[0065] In one embodiment, the Si-doped InN layer 513 is prepared by the following method:
[0066] The temperature of the reaction chamber is controlled at 700℃~900℃, the pressure is controlled at 50torr~300torr, and a mixed atmosphere of N2 and NH3 is introduced to grow a Si-doped InN layer.
[0067] In one embodiment, the InGaN layer 514 is prepared by the following method:
[0068] The temperature of the reaction chamber is controlled at 700℃~900℃, the pressure is controlled at 50torr~300torr, and a mixed atmosphere of N2 and NH3 is introduced to grow an InGaN layer.
[0069] In one embodiment, the quantum barrier layer 520 is prepared by the following method:
[0070] The temperature of the reaction chamber was controlled at 800℃~1000℃, and the pressure was controlled at 50 torr~500 torr. N source, Al source, and Ga source were introduced to grow AlGaN quantum barrier layer.
[0071] S25. Deposit an electron blocking layer 600 on the multi-quantum well layer 500.
[0072] In one embodiment, the temperature of the reaction chamber is controlled at 900℃~1000℃, the pressure is controlled at 100torr~300torr, and N source, Al source, Ga source and In source are introduced to grow an AlInGaN electron blocking layer with a thickness of 10nm~40nm.
[0073] S26. Deposit a P-type GaN layer 700 on the electron blocking layer 600.
[0074] In one embodiment, the temperature of the reaction chamber is controlled at 900℃~1050℃, and the pressure is controlled at 100 torr~600 torr. An N source, a Ga source, and a Mg source are introduced to grow a P-type GaN layer with a thickness of 10nm~5nm. Preferably, the Mg doping concentration is 1×10⁻⁶. 19 atoms / cm 3 ~1×10 21 atoms / cm 3 .
[0075] Accordingly, the present invention also provides an LED comprising the aforementioned light-emitting diode epitaxial wafer. The photoelectric efficiency of the LED is effectively improved, and other electrical properties are also excellent.
[0076] The present invention is further illustrated below with specific embodiments:
[0077] Example 1
[0078] This embodiment provides a light-emitting diode epitaxial wafer, including a substrate, on which a buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially disposed;
[0079] The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
[0080] The thickness of the BN layer is 20 nm.
[0081] The AlInGaN layer has a thickness of 2.5 nm, with the Al content gradually decreasing from 0.05 to 0.01 along the growth direction and the In content gradually increasing from 0.05 to 0.15 along the growth direction.
[0082] The thickness of the Si-doped InN layer is 1.5 nm, and the Si doping concentration is 5 × 10⁻⁶. 17 atoms / cm 3 .
[0083] The InGaN layer has a thickness of 3.5 nm and an In composition of 0.15.
[0084] Example 2
[0085] This embodiment provides a light-emitting diode epitaxial wafer, including a substrate, on which a buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially disposed;
[0086] The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
[0087] The thickness of the BN layer is 5 nm.
[0088] The AlInGaN layer has a thickness of 1 nm, with the Al content gradually decreasing from 0.01 to 0.01 along the growth direction and the In content gradually increasing from 0.05 to 0.5 along the growth direction.
[0089] The thickness of the Si-doped InN layer is 1 nm, and the Si doping concentration is 1 × 10⁻⁶. 17 atoms / cm 3 .
[0090] The InGaN layer has a thickness of 1 nm and an In composition of 0.1.
[0091] Example 3
[0092] This embodiment provides a light-emitting diode epitaxial wafer, including a substrate, on which a buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially disposed;
[0093] The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
[0094] The thickness of the BN layer is 50 nm.
[0095] The AlInGaN layer has a thickness of 10 nm, with the Al content gradually decreasing from 0.05 to 0.01 along the growth direction and the In content gradually increasing from 0.05 to 0.15 along the growth direction.
[0096] The thickness of the Si-doped InN layer is 5 nm, and the Si doping concentration is 1 × 10⁻⁶. 18 atoms / cm 3 .
[0097] The InGaN layer has a thickness of 10 nm and an In composition of 0.5.
[0098] Comparative Example 1
[0099] This comparative example provides a light-emitting diode epitaxial wafer. The difference between this example and the other examples of Example 1 is that the multi-quantum well layer is an InGaN quantum well layer / AlGaN quantum barrier layer, and the rest are the same as in Example 1.
[0100] Comparative Example 2
[0101] This comparative example provides a light-emitting diode epitaxial wafer. The difference between this example and the other examples of Example 1 is that the composite quantum well layer includes an AlInGaN layer, a Si-doped InN layer and an InGaN layer stacked sequentially, but does not include a BN layer. The rest is the same as in Example 1.
[0102] Comparative Example 3
[0103] This comparative example provides a light-emitting diode epitaxial wafer. The difference between this example and the other examples of Example 1 is that the composite quantum well layer includes a BN layer, a Si-doped InN layer, and an InGaN layer stacked sequentially, but does not include an AlInGaN layer. The rest is the same as in Example 1.
[0104] Comparative Example 4
[0105] This comparative example provides a light-emitting diode epitaxial wafer. The difference between this example and the other examples of Example 1 is that the composite quantum well layer includes a BN layer, an AlInGaN layer, and an InGaN layer stacked sequentially, but does not include a Si-doped InN layer. The rest is the same as in Example 1.
[0106] The light-emitting diode epitaxial wafers prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were fabricated into 10mil×24mil chips using the same chip process conditions. 300 LED chips were randomly selected from each example and tested at a current of 120mA / 60mA. With Comparative Example 1 as a reference, the luminous efficiency improvement rate of each example and comparative example was calculated. The specific test results are shown in Table 1.
[0107] Table 1. Performance test results of LEDs prepared in Examples 1-3 and Comparative Examples 1-4
[0108]
[0109]
[0110] As can be seen from the above results, the present invention, by providing a composite quantum well layer with a specific structure on the substrate and growing the composite quantum well layer and quantum barrier layer with multiple periods, can improve the quantum confinement effect, localize electrons and holes in multiple quantum wells, thereby improving the overlap of electron and hole wave functions, reducing the defect density of the quantum well layer, improving the crystal quality of the quantum well layer, reducing the polarization effect of the quantum well layer, and improving the radiative recombination efficiency of the multiple quantum well layer.
[0111] The above description is a preferred embodiment of the invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the invention, and these improvements and modifications are also considered to be within the scope of protection of the invention.
Claims
1. A light-emitting diode epitaxial wafer, characterized in that, The substrate includes a buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer, which are sequentially disposed on the substrate. The multi-quantum well layer includes multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer includes a BN layer, an AlInGaN layer, a Si-doped InN layer, and an InGaN layer stacked sequentially. The thickness of the AlInGaN layer is 0.1 nm to 10 nm; The Al composition of the AlInGaN layer is 0.01~0.1; the In composition of the AlInGaN layer is 0.01~0.
5. The Al content of the AlInGaN layer gradually decreases along the growth direction, while the In content gradually increases along the growth direction. The BN layer causes dislocation torsion, the AlInGaN layer reduces the lattice mismatch between the InGaN quantum well layer and the AlGaN barrier layer by changing its composition, and the Si-doped InN layer reduces the polarization effect of the quantum well layer by controlling the piezoelectric field of the quantum well layer through Si doping.
2. The light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The thickness of the BN layer is 5nm to 50nm.
3. The light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The thickness of the Si-doped InN layer is 0.1 nm to 5 nm; The Si doping concentration of the Si-doped InN layer is 1×10⁻⁶. 17 atoms / cm 3 ~1×10 18 atoms / cm 3 .
4. The light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The thickness of the InGaN layer is 0.5 nm to 10 nm; The In composition of the InGaN layer is 0.01~0.
5.
5. The light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The multi-quantum well layer comprises 1 to 20 periodically alternating composite quantum well layers and quantum barrier layers.
6. The light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The quantum barrier layer is an AlGaN layer, and the Al composition of the AlGaN layer is 0.01~0.
5.
7. A method for fabricating a light-emitting diode epitaxial wafer as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Prepare the substrate; S2. A buffer layer, an undoped GaN layer, an N-type GaN layer, a multiple quantum well layer, an electron blocking layer, and a P-type GaN layer are sequentially deposited on the substrate. The multi-quantum well layer comprises multiple alternating layers of composite quantum well layers and quantum barrier layers. The composite quantum well layer comprises sequentially stacked BN layers, AlInGaN layers, Si-doped InN layers, and InGaN layers.
8. An LED, characterized in that, The LED includes a light-emitting diode epitaxial wafer as described in any one of claims 1 to 6.