Dual-band light emitting diode epitaxial wafer and method of manufacturing the same

Abstract

The present application relates to the technical field of light emitting diode, and discloses a double-waveband light emitting diode epitaxial wafer and a preparation method thereof.The double-waveband light emitting diode epitaxial wafer comprises a substrate, a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer which are sequentially stacked on the substrate; the light emitting wavelength of the first multiple quantum well layer is greater than that of the second multiple quantum well layer; the electron dispersion layer comprises a Si-doped Al x1 Ga 1‑x1 N layer; and the hole injection layer comprises a Mg-doped In y4 Ga 1‑y4 N layer. According to the present application, two wavebands of LED light sources can be excited by a single LED chip, the use of multiple LED chips with different light emitting wavebands is reduced, the use of fluorescent powder in a white light LED backlight light source is reduced, and the light emitting efficiency and luminance are improved.

Description

Technical Field

[0001] This invention relates to the technical field of light-emitting diodes, and more particularly to a dual-band light-emitting diode epitaxial wafer and its fabrication method. Background Technology

[0002] Light Emitting Diode (LED) is a new type of energy-saving and environmentally friendly light source that has received considerable attention in recent years. Through extensive research and experimentation, semiconductor lighting technology has made rapid progress, truly realizing the commercialization of semiconductor lighting. Various types of LEDs are widely used in indication, display, backlighting, projection, and other fields.

[0003] Currently, there are two types of LED backlight sources used in displays: RGB LEDs and white LEDs. RGB LEDs encapsulate three monochromatic LED chips—blue, green, and red—together, while white LEDs are formed by combining monochromatic LED chips with phosphors, such as combining a monochromatic blue chip with green and red phosphors, or a monochromatic blue chip with yellow phosphors. Among these, RGB tri-color LED backlight sources offer the best display effect but are more expensive. White LEDs require phosphors, but different phosphor schemes have significant differences in color gamut, and the uniformity of the phosphor mixed with the adhesive is difficult to control, leading to problems such as less than ideal color rendering.

[0004] Therefore, reducing the reliance of LED backlight sources on multiple LED chips with different emission wavelengths, reducing the use of phosphors in white LED backlight sources, and simultaneously ensuring good color rendering are technical problems that need to be solved in current LED backlight applications. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a dual-band light-emitting diode epitaxial wafer and its preparation method, which can reduce the dependence of LED backlight source on multiple LED chips with different light-emitting bands, reduce the use of phosphor in white LED backlight source, and improve the luminous efficiency and color rendering index of dual-band LED device.

[0006] To solve the above-mentioned technical problems, the first aspect of the present invention provides a dual-band light-emitting diode epitaxial wafer, comprising a substrate, and a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer sequentially stacked on the substrate. Wherein, the emission wavelength of the first quantum well layer is greater than the emission wavelength of the second quantum well layer; The electron dispersion layer is Si-doped Al. x1 Ga1-x1 N-layer and In y3 Ga 1-y3 A superlattice structure formed by N layers of periodically alternating stacks; The first electron blocking layer includes Al x3 Ga 1-x3 N layers; The second electron blocking layer includes Al x4 Ga 1-x4 N layers; The hole injection layer is Al. x2 Ga 1-x2 N-layer and Mg-doped In y4 Ga 1-y4 A superlattice structure formed by the periodic alternation of N layers.

[0007] As an improvement to the above scheme, the first multi-quantum well layer is a green light multi-quantum well layer, wherein the green light multi-quantum well layer is an In-type layer grown in a periodically alternating manner. y1 Ga 1-y1 The superlattice structure formed by the N quantum well layer and the first GaN quantum barrier layer has a period number of 2 to 10. The second multiple quantum well layer is a blue light multiple quantum well layer; the blue light multiple quantum well layer is an In-type layer grown in a periodic alternating pattern. y2 Ga 1-y2 The superlattice structure formed by the N quantum well layer and the second GaN quantum barrier layer has a period number of 2 to 12.

[0008] As an improvement to the above solution, the In y1 Ga 1-y1 The N quantum well layer is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In composition is 0.22≤y1≤0.28. The first GaN quantum barrier layer is a single-layer GaN structure doped with Si or a multilayer GaN structure doped with Si, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 ; The In y1 Ga 1-y1 The growth thickness of the N quantum well layer is 2nm~5nm; the growth thickness of the first GaN quantum barrier layer is 5nm~16nm; The In y2 Ga 1-y2The N-quantum well layer is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In content is 0.06 ≤ y² ≤ 0.19; the second GaN quantum barrier layer is a Si-doped GaN monolayer or Si-doped GaN multilayer structure, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 ; The In y2 Ga 1-y2 The growth thickness of the N quantum well layer is 2nm~5nm; the growth thickness of the second GaN quantum barrier layer is 5nm~16nm.

[0009] As an improvement to the above scheme, the number of periods in the electron dispersion layer is 2 to 30; Wherein, the Si-doped Al x1 Ga 1-x1 In the N-layer, the Al composition percentage is 0.10 ≤ x1 ≤ 0.90, and the Si doping concentration is 2.0 × 10⁻⁶. 17 / cm 3 ~8.8×10 18 / cm 3 ; The In y3 Ga 1-y3 No intentional doping is performed in the N layer, and the In component ratio is 0.003≤y3≤0.10; The Si-doped Al x1 Ga 1-x1 The N-layer has a growth thickness of 0.2 nm to 20 nm; the In y3 Ga 1-y3 The growth thickness of the N layer ranges from 0.2 nm to 20 nm.

[0010] As an improvement to the above scheme, the number of cycles of the hole injection layer is 2 to 18; Wherein, the Al x2 Ga 1-x2 No intentional doping is performed in the N layer, and the Al component percentage is 0.16 ≤ x2 < 1; the Mg-doped In y4 Ga 1-y4 In the N-layer, the In composition percentage is 0.01 ≤ y4 ≤ 0.16, and the Mg doping concentration is 2 × 10⁻⁶. 18 / cm 3 ~5×10 19 / cm 3 ; The Al x2 Ga 1-x2The N-layer has a growth thickness of 0.2 nm to 3.6 nm; the Mg-doped In y4 Ga 1-y4 The growth thickness of the N layer ranges from 0.2 nm to 3.6 nm.

[0011] As an improvement to the above scheme, the first electron blocking layer is Al. x3 Ga 1-x3 N single-layer structure or Al x3 Ga 1-x3 The structure has N layers, and the second electron blocking layer is Al. x4 Ga 1-x4 N single-layer structure or Al x4 Ga 1-x4 Multi-layer structure; The growth thickness of the first electron blocking layer is greater than or equal to the growth thickness of the second electron blocking layer.

[0012] As an improvement to the above scheme, the growth thickness of the first electron blocking layer is 0.3 nm to 30 nm; The thickness of the second electron blocking layer is 0.3 nm to 30 nm. The proportion of Al component in the first electron blocking layer is 0.03≤x3≤0.86; the proportion of Al component in the second electron blocking layer is 0.03≤x4≤0.86.

[0013] As an improvement to the above scheme, the first N-type semiconductor layer is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c1; the second N-type semiconductor layer is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c2. It satisfies: c1≥c2.

[0014] As an improvement to the above scheme, c1 satisfies: 3.6 × 10 18 / cm 3 ≤c1≤5.8×10 20 / cm 3 ; The c2 satisfies: 3.6 × 10 18 / cm 3 ≤c2≤5.8×10 20 / cm 3 ; The thickness of the first N-type semiconductor layer is 0.3 μm to 6.8 μm; the thickness of the second N-type semiconductor layer is 0.3 μm to 6.8 μm. The P-type semiconductor layer is Mg-doped Al. a In b Ga1-a-b N layers; wherein the Al component has a proportion of 0 < a ≤ 0.3, the In component has a proportion of 0 < b ≤ 0.3, and the Mg doping concentration is 2.0 × 10⁻⁶. 19 / cm 3 ~6.8×10 21 / cm 3 The growth thickness of the P-type semiconductor layer is 5nm~500nm.

[0015] A second aspect of the present invention provides a method for fabricating the epitaxial wafer of the dual-band light-emitting diode, comprising the following steps: Provide a substrate; A first N-type semiconductor layer is deposited on the substrate; An electron dispersion layer is deposited on the first N-type semiconductor layer; A second N-type semiconductor layer is deposited on the electron dispersion layer; A first electron blocking layer is deposited on the second N-type semiconductor layer; A first multiple quantum well layer is deposited on the first electron blocking layer; A second electron blocking layer is deposited on the first multi-quantum-well layer; A second multiple quantum well layer is deposited on the second electron blocking layer; A hole injection layer is deposited on the second multiple quantum well layer; A P-type semiconductor layer is deposited on the hole injection layer; Wherein, the emission wavelength of the first quantum well layer is greater than the emission wavelength of the second quantum well layer; The electron dispersion layer is Si-doped Al. x1 Ga 1-x1 N-layer and In y3 Ga 1-y3 A superlattice structure formed by N layers of periodically alternating stacks; The first electron blocking layer includes Al x3 Ga 1-x3 N layers; The second electron blocking layer includes Al x4 Ga 1-x4 N layers; The hole injection layer is Al. x2 Ga 1-x2 N-layer and Mg-doped In y4 Ga 1-y4 A superlattice structure formed by the periodic alternation of N layers.

[0016] Implementing this invention has the following beneficial effects: In this invention, a first quantum well layer and a second quantum well layer are disposed between the second N-type semiconductor layer and the P-type semiconductor layer, and four electron blocking layer structures are disposed in the epitaxial wafer of the dual-band light-emitting diode. This allows some electrons to be trapped in the first quantum well layer and recombine with holes, while others can cross the intermediate barrier and continue to enter the second quantum well layer. At the same time, holes injected from the P side first enter the second quantum well layer, some recombine, and others continue to be transported to the N side and reach the first quantum well layer. This enables a single LED chip to excite two wavelengths of LED light source, which can reduce the dependence of LED backlight source on multiple LED chips with different light emission bands, reduce the use of phosphor in white LED backlight source, and improve luminous efficiency, luminous brightness and color rendering index. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a dual-band light-emitting diode epitaxial wafer according to the present invention; Figure 2 This is a schematic diagram of the structure of the first multi-quantum well layer in this invention; Figure 3 This is a schematic diagram of the structure of the second multi-quantum well layer in this invention; Figure 4 This is a schematic diagram of the electron dispersion layer structure in this invention; Figure 5 This is a schematic diagram of the hole injection layer in this invention.

[0018] Figure label: 1-Substrate; 2-First N-type semiconductor layer; 3-Electron dispersion layer; 31-Si-doped Al x1 Ga 1-x1 N layers; 32-In y3 Ga 1-y3 N-layer; 4-Second N-type semiconductor layer; 5-First electron blocking layer; 6-First multiple quantum well layer; 61-In y1 Ga 1-y1 N-Quantum well layer; 62-First GaN quantum barrier layer; 7-Second electron blocking layer; 8-Second multiple quantum well layer; 81-In y2 Ga 1-y2 N-Quantum well layer; 82-Second GaN quantum barrier layer; 9-Hole injection layer; 91-Al x2 Ga 1-x2 N-layer; 92-Mg-doped In y4 Ga 1-y4 N-layer; 10-P type semiconductor layer. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments.

[0020] In the description of this application, it is necessary to understand that the orientation or positional relationship indicated by terms such as "upper", "lower", "top", "bottom", "inner", and "outer" are based on the orientation or positional relationship shown in the accompanying drawings. They are intended only to facilitate the description of the present invention and to simplify the description, and are not intended to indicate or imply that the components referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0021] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the particular range. The range defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range.

[0022] To address the above problems, the first aspect of this invention provides a dual-band light-emitting diode epitaxial wafer. (See attached image.) Figure 1 The substrate includes a substrate 1, on which a first N-type semiconductor layer 2, an electron dispersion layer 3, a second N-type semiconductor layer 4, a first electron blocking layer 5, a first multiple quantum well layer 6, a second electron blocking layer 7, a second multiple quantum well layer 8, a hole injection layer 9, and a P-type semiconductor layer 10 are sequentially stacked. The emission wavelength of the first quantum well layer 6 is greater than that of the second quantum well layer 8.

[0023] In this invention, a first quantum well layer 6 and a second quantum well layer 8 are disposed between the second N-type semiconductor layer 4 and the P-type semiconductor layer 10, and four electron blocking layer structures are disposed in the epitaxial wafer of the dual-band light-emitting diode. This allows some electrons to be trapped in the first quantum well layer 6 and recombine with holes, while others can cross the intermediate barrier and continue to enter the second quantum well layer 8. At the same time, holes injected from the P side first enter the second quantum well layer 8, some recombine, and others continue to be transported to the N side and reach the first quantum well layer 6. This enables a single LED chip to excite two wavelengths of LED light source, reducing the dependence of the LED backlight source on multiple LED chips with different light emission bands, thereby reducing the cost of the RGB LED backlight source and reducing the use of phosphor in the white LED backlight source.

[0024] Furthermore, the electron blocking layer specifically includes an electron dispersion layer 3 disposed between the first N-type semiconductor layer 2 and the second N-type semiconductor layer 4, a first electron blocking layer 5 disposed between the second N-type semiconductor layer 4 and the first multi-quantum well layer 6, a second electron blocking layer 7 disposed between the first multi-quantum well layer 6 and the second multi-quantum well layer 8, and a hole injection layer 9 disposed between the second multi-quantum well layer 8 and the P-type semiconductor layer 10. Unlike traditional LED epitaxial wafers where the electron blocking layer is only designed after the multi-quantum well layer and before the P-type semiconductor layer 10, the four electron blocking layers disposed at different positions work together to regulate the distribution of electrons and holes in the two sets of multi-quantum well layers through multiple potential barriers, thereby preventing electrons from overflowing from the multi-quantum well layer. At the same time, it takes into account both electron confinement and hole injection, which can reduce the blocking effect of the electron blocking layer structure on the injection of holes from the P-type semiconductor layer 10 into the multi-quantum well layer, improve the hole injection efficiency of the P-type semiconductor layer 10, and thus improve the luminous efficiency and color rendering index.

[0025] The electron dispersion layer 3 includes Si-doped Al x1 Ga 1-x1 The N-layer, utilizing the relatively wide bandgap of AlGaN, can form an electron barrier to pre-regulate electron transport from the first N-type semiconductor layer 2 to the second N-type semiconductor layer 4 and subsequent active regions; simultaneously, it can maintain the N-type conductivity of the electron dispersion layer 3, adjusting the electron concentration and energy distribution entering the first multiple quantum well layer 6 and the second multiple quantum well layer 8. The first electron blocking layer 5 includes Al... x3 Ga 1-x3 The N-layer can form an electron injection barrier between the second N-type semiconductor layer 4 and the first multiple quantum well layer 6, thereby controlling the number and energy of electrons injected into the first multiple quantum well layer 6 from the N side and preventing excessive electron injection; the second electron blocking layer 7 includes Al x4 Ga 1-x4 The N-layer can form an interstage electron barrier between the first quantum well layer 6 and the second quantum well layer 8, thereby shunting and controlling the electrons transported to the P-side after passing through the first quantum well layer 6. This allows some electrons to remain in the first quantum well layer 6 to participate in radiative recombination, while simultaneously allowing some electrons to cross the second electron barrier layer 7 into the second quantum well layer 8, thus adjusting the electron distribution ratio between the two quantum well emitting regions. The hole injection layer 9 includes Mg-doped In. y4 Ga 1-y4 The N-layer can improve the effective supply of holes on the P-side, adjust the hole transport barrier between the P-type semiconductor layer 10 and the second multiple quantum well layer 8, and improve the injection and transport capability of holes from the P-type semiconductor layer 10 to the second multiple quantum well layer 8 and further to the first multiple quantum well layer 6.

[0026] In some specific and preferred embodiments, the first quantum well layer 6 is a green quantum well layer and the second quantum well layer 8 is a blue quantum well layer.

[0027] Preferably, please refer to Figure 2 The green light multi-quantum well layer is an In-type layer grown in a periodic alternating pattern. y1 Ga 1-y1 The superlattice structure formed by the N quantum well layer 61 and the first GaN quantum barrier layer 62 has a period number of 2 to 10, which can be 2, 4, 6, 8, or 10, but is not limited thereto.

[0028] Furthermore, the In y1 Ga 1-y1 The N-quantum well layer 61 is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In content is 0.22 ≤ y1 ≤ 0.28; the first GaN quantum barrier layer 62 is a Si-doped GaN monolayer or Si-doped GaN multilayer structure, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 .

[0029] Furthermore, the In y1 Ga 1-y1 The thickness of the N quantum well layer 61 is 2nm~5nm; the thickness of the first GaN quantum barrier layer 62 is 5nm~16nm, and the In content is controlled based on a specific In composition ratio. y1 Ga 1-y1 The growth thickness of the N-quantum well layer 61 and the first GaN quantum barrier layer 62 is beneficial to improving the recombination of electrons and holes. For example, the In... y1 Ga 1-y1 The growth thickness of the N quantum well layer 61 is 2nm, 2.5nm, 3nm, 3.5nm, 4nm, 4.5nm, or 5nm, but is not limited thereto; the growth thickness of the first GaN quantum barrier layer 62 is 5nm, 7nm, 9nm, 11nm, 13nm, 15nm, or 16nm, but is not limited thereto.

[0030] Preferably, please refer to Figure 3 The blue light multi-quantum well layer is an In-type layer grown in a periodic alternating pattern. y2 Ga 1-y2 The superlattice structure formed by the N quantum well layer 81 and the second GaN quantum barrier layer 82 has a period number of 2 to 12, which can be 2, 4, 6, 8, 10, or 12, but is not limited thereto.

[0031] Furthermore, the Iny2 Ga 1-y2 The N-quantum well layer 81 is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In content is 0.06 ≤ y² ≤ 0.19; the second GaN quantum barrier layer 82 is a Si-doped GaN monolayer or Si-doped GaN multilayer structure, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 .

[0032] Furthermore, the In y2 Ga 1-y2 The thickness of the N-quantum well layer 81 is 2 nm to 5 nm; the thickness of the second GaN quantum barrier layer 82 is 5 nm to 16 nm. For example, the In... y2 Ga 1-y2 The growth thickness of the N quantum well layer 81 is 2nm, 2.5nm, 3nm, 3.5nm, 4nm, 4.5nm, or 5nm, but is not limited thereto; the growth thickness of the second GaN quantum barrier layer 82 is 5nm, 7nm, 9nm, 11nm, 13nm, 15nm, or 16nm, but is not limited thereto.

[0033] Preferably, please refer to Figure 4 The electron dispersion layer 3 is Si-doped Al x1 Ga 1-x1 N-layer 31 and In y3 Ga 1-y3 The superlattice structure is formed by periodically alternating N layers (32), with a period number of 2 to 30, exemplarily 2, 5, 10, 15, 20, 25, and 30, but not limited to these. In this invention, the electron dispersion layer 3 is doped with Si, which can provide some electrons to the first quantum well layer 6 and the second quantum well layer 8 and participate in radiative recombination luminescence. Simultaneously, the electron dispersion layer 3 is designed as an AlGaN / InGaN superlattice material, wherein the low bandgap InGaN material can store some electrons, improving the electron migration rate, thereby controlling the electron concentration distribution in the first quantum well layer 6 and the second quantum well layer 8.

[0034] Furthermore, the Si-doped Al x1 Ga 1-x1 In layer N31, the Al composition percentage is 0.10 ≤ x1 ≤ 0.90, and the Si doping concentration is 2.0 × 10⁻⁶. 17 / cm 3 ~8.8×10 18 / cm 3For example, x1 can be 0.10, 0.30, 0.50, 0.70, or 0.90, but is not limited thereto; the Si doping concentration is 2.0 × 10⁻⁶. 17 / cm 3 5.2×10 17 / cm 3 8.2×10 17 / cm 3 1.2×10 18 / cm 3 3.2×10 18 / cm 3 5.2×10 18 / cm 3 8.8×10 18 / cm 3 However, it is not limited to this. The In mentioned above... y3 Ga 1-y3 No intentional doping is performed in the N layer 32, and the In component ratio is 0.003≤y3≤0.10; for example, y3 can be 0.003, 0.005, 0.007, 0.009, 0.10, but is not limited thereto.

[0035] Furthermore, the Si-doped Al x1 Ga 1-x1 The growth thickness of layer N31 is 0.2nm to 20nm, and can be 0.2nm, 1nm, 5nm, 10nm, 15nm, or 20nm, but is not limited thereto; the In y3 Ga 1-y3 The growth thickness of the N-layer 32 is 0.2nm to 20nm, and can be 0.2nm, 1nm, 5nm, 10nm, 15nm, or 20nm, but is not limited to these.

[0036] In this invention, the first electron blocking layer 5 controls the number and energy of electrons entering the first quantum well layer 6; the second electron blocking layer 7 isolates the first quantum well layer 6 and the second quantum well layer 8 and regulates electron transport between them. Preferably, the first electron blocking layer 5 is Al. x3 Ga 1-x3 N single-layer structure or Al x3 Ga 1-x3 The structure has N layers, and the second electron blocking layer 7 is Al. x4 Ga 1-x4 N single-layer structure or Al x4 Ga 1-x4In the N-layer structure, the growth thickness of the first electron blocking layer 5 is greater than or equal to the growth thickness of the second electron blocking layer 7, which can further regulate the distribution of electron and hole concentrations in the first quantum well layer 6 and the second quantum well layer 8, so as to improve the electron-hole matching degree in the first quantum well layer 6 and the second quantum well layer 8, thereby improving the luminous efficiency of the blue-green dual-band LED chip.

[0037] Furthermore, the growth thickness of the first electron blocking layer 5 is 0.3nm to 30nm, and can be, for example, 0.3nm, 1nm, 5nm, 10nm, 15nm, 20nm, 25nm, or 30nm, but is not limited thereto. The growth thickness of the second electron blocking layer 7 is 0.3nm to 30nm, and can be, for example, 0.3nm, 1nm, 5nm, 10nm, 15nm, 20nm, 25nm, or 30nm, but is not limited thereto.

[0038] Furthermore, in the first electron blocking layer 5, the proportion of Al component is 0.03≤x3≤0.86, and x3 can be 0.03, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.86, but is not limited thereto; in the second electron blocking layer 7, the proportion of Al component is 0.03≤x4≤0.86, and x4 can be 0.03, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.86, but is not limited thereto.

[0039] Preferably, please refer to Figure 5 The hole injection layer 9 is Al x2 Ga 1-x2 N-layer 91 and Mg-doped In y4 Ga 1-y4 The superlattice structure is formed by periodically alternating N layers 92, with a period number of 2 to 18, exemplarily 2, 5, 10, 15, and 18, but not limited to these. In this invention, the hole injection layer 9 is doped with Mg, which can provide some holes to the active region to participate in radiative recombination luminescence; at the same time, the hole injection layer 9 is designed as an AlGaN / InGaN superlattice structure, and the low bandgap InGaN material can store some holes, improve the hole migration rate, thereby further controlling the hole concentration distribution in the first multiple quantum well layer 6 and the second multiple quantum well layer 8, and suppressing electron overflow into the P-type semiconductor layer 10.

[0040] Furthermore, the Al x2 Ga 1-x2 In layer 91, no intentional doping is performed, and the Al component percentage is 0.16 ≤ x2 < 1. For example, x2 can be 0.16, 0.3, 0.5, 0.7, 0.9, or 0.99, but is not limited to these. The Mg-doped In...y4 Ga 1-y4 In the N-layer 92, the In composition ratio is 0.01≤y4≤0.16, and the Mg doping concentration is 2×10⁻⁶. 18 / cm 3 ~5×10 19 / cm 3 For example, y4 can be 0.01, 0.05, 0.1, 0.15, or 0.16, but is not limited to these; the Mg doping concentration is 2 × 10⁻⁶. 18 / cm 3 5×10 18 / cm 3 1×10 19 / cm 3 3×10 19 / cm 3 5×10 19 / cm 3 However, it is not limited to this.

[0041] Furthermore, the Al x2 Ga 1-x2 The growth thickness of the N-layer 91 is 0.2 nm to 3.6 nm, and exemplary thicknesses can be 0.2 nm, 0.5 nm, 1 nm, 1.5 nm, 2 nm, 2.5 nm, 3 nm, and 3.6 nm, but are not limited thereto; the Mg-doped In y4 Ga 1-y4 The growth thickness of the N-layer 92 is 0.2nm to 3.6nm, and can be 0.2nm, 0.5nm, 1nm, 1.5nm, 2nm, 2.5nm, 3nm, or 3.6nm, but is not limited to these.

[0042] Preferably, the first N-type semiconductor layer 2 is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c1; the second N-type semiconductor layer 4 is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c2; satisfying c1≥c2, the distribution of electron and hole concentrations in the first quantum well layer 6 and the second quantum well layer 8 can be further controlled to improve the electron-hole matching degree in the first quantum well layer 6 and the second quantum well layer 8, thereby improving the luminous efficiency of the blue-green dual-band LED chip.

[0043] Furthermore, c1 satisfies: 3.6 × 10 18 / cm 3 ≤c1≤5.8×10 20 / cm 3 c1 can be 3.6 × 10 for example. 18 / cm 3 5.6×1018 / cm 3 1.6×10 19 / cm 3 5.6×10 19 / cm 3 1.6×10 20 / cm 3 5.8×10 20 / cm 3 However, it is not limited to this; the c2 satisfies: 3.6 × 10 18 / cm 3 ≤c2≤5.8×10 20 / cm 3 For example, c2 can be 3.6 × 10 18 / cm 3 5.6×10 18 / cm 3 1.6×10 19 / cm 3 5.6×10 19 / cm 3 1.6×10 20 / cm 3 5.8×10 20 / cm 3 However, it is not limited to this.

[0044] Furthermore, the growth thickness of the first N-type semiconductor layer 2 is 0.3μm to 6.8μm, and can be 0.3μm, 0.5μm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, or 6.8μm, but is not limited thereto; the growth thickness of the second N-type semiconductor layer 4 is 0.3μm to 6.8μm, and can be 0.3μm, 0.5μm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, or 6.8μm, but is not limited thereto.

[0045] Preferably, the P-type semiconductor layer 10 is Mg-doped Al. a In b Ga 1-a-b N layers; wherein the Al component has a proportion of 0 < a ≤ 0.3, the In component has a proportion of 0 < b ≤ 0.3, and the Mg doping concentration is 2.0 × 10⁻⁶. 19 / cm 3 ~6.8×10 21 / cm 3 For example, a can be 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, or 0.3, but is not limited thereto; b can be 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, or 0.3, but is not limited thereto; the Mg doping concentration is 2.0 × 10⁻⁶.19 / cm 3 5.0×10 19 / cm 3 1.0×10 20 / cm 3 5.0×10 20 / cm 3 1.0×10 21 / cm 3 5.0×10 21 / cm 3 6.8×10 21 / cm 3 However, it is not limited to this.

[0046] Furthermore, the growth thickness of the P-type semiconductor layer 10 is 5nm to 500nm, and can be, for example, 5nm, 50nm, 100nm, 200nm, 300nm, 400nm, or 500nm, but is not limited thereto.

[0047] Accordingly, a second aspect of the present invention provides a method for fabricating the dual-band light-emitting diode epitaxial wafer, comprising the following steps: (1) Provide a substrate 1; (2) A first N-type semiconductor layer 2 is deposited on the substrate 1; (3) An electron dispersion layer 3 is deposited on the first N-type semiconductor layer 2; (4) Deposit a second N-type semiconductor layer 4 on the electron dispersion layer 3; (5) Deposit a first electron blocking layer 5 on the second N-type semiconductor layer 4; (6) Deposit a first multiple quantum well layer 6 on the first electron blocking layer 5; (7) Deposit a second electron blocking layer 7 on the first multiple quantum well layer 6; (8) Deposit a second multiple quantum well layer 8 on the second electron blocking layer 7; (9) Deposit a hole injection layer 9 on the second multiple quantum well layer 8; (10) Deposit a P-type semiconductor layer 10 on the hole injection layer 9; The emission wavelength of the first quantum well layer 6 is greater than that of the second quantum well layer 8.

[0048] Preferably, in step (2), the growth temperature of the first N-type semiconductor layer 2 is 900℃~1250℃, and the growth pressure is 30 torr~360 torr.

[0049] Preferably, in step (3), the Si-doped Al x1 Ga1-x1 The growth temperature of N layer 31 is 800℃~1250℃, and the growth pressure is 30 torr~360 torr; the In y3 Ga 1-y3 The growth temperature of N-layer 32 is 750℃~1200℃, and the growth pressure is 30 torr~360 torr.

[0050] Preferably, in step (4), the growth temperature of the second N-type semiconductor layer 4 is 900℃~1250℃, and the growth pressure is 30 torr~360 torr.

[0051] Preferably, in step (5), the growth temperature of the first electron blocking layer 5 is 730℃~1000℃, and the growth pressure is 30 torr~360 torr.

[0052] Preferably, in step (6), the In y1 Ga 1-y1 The growth temperature of the N quantum well layer 61 is 680℃~920℃, and the growth pressure is 30 torr~360 torr; the growth temperature of the first GaN quantum barrier layer 62 is 780℃~980℃, and the growth pressure is 30 torr~360 torr.

[0053] Preferably, in step (7), the growth temperature of the second electron blocking layer 7 is 730℃~1000℃, and the growth pressure is 30 torr~360 torr.

[0054] Preferably, in step (8), the In y2 Ga 1-y2 The growth temperature of the N quantum well layer 81 is 720℃~920℃, and the growth pressure is 30 torr~360 torr; the growth temperature of the second GaN quantum barrier layer 82 is 780℃~980℃, and the growth pressure is 30 torr~360 torr.

[0055] Preferably, in step (9), the Al x2 Ga 1-x2 The growth temperature of the N-layer 91 is 750℃~1050℃, and the growth pressure is 30 torr~360 torr; the Mg-doped In y4 Ga 1-y4 The growth temperature of N-layer 92 is 750℃~1050℃, and the growth pressure is 30 torr~360 torr.

[0056] Preferably, in step (10), the growth temperature of the P-type semiconductor layer 10 is 880℃~1080℃, and the growth pressure is 30 torr~360 torr.

[0057] It is understood that the substrate 1 can be selected from sapphire substrate, silicon carbide substrate, silicon substrate, etc.; the first N-type semiconductor layer 2, electron dispersion layer 3, second N-type semiconductor layer 4, first electron blocking layer 5, first multiple quantum well layer 6, second electron blocking layer 7, second multiple quantum well layer 8, hole injection layer 9 and P-type semiconductor layer 10 are all grown using existing processes and materials, and will not be further described in this invention.

[0058] The present invention will be further described below with reference to specific embodiments: Example 1 This embodiment provides a dual-band light-emitting diode epitaxial wafer, including a substrate, on which a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked. The first multiple quantum well layer is a green light multiple quantum well layer, and the green light multiple quantum well layer is a periodically alternating In... y1 Ga 1-y1 The superlattice structure formed by the N quantum well layer and the first GaN quantum barrier layer has a period number of 7; In y1 Ga 1-y1 The N-quantum well layer is an undoped InGaN layer with an In content of y1 = 0.25; the first GaN quantum barrier layer is a Si-doped GaN layer with a Si doping concentration of 5.7 × 10⁻⁶. 17 / cm 3 In a single cycle, In y1 Ga 1-y1 The thickness of the N quantum well layer is 4 nm; the thickness of the first GaN quantum barrier layer is 10 nm. The second quantum well layer is a blue quantum well layer, which is a periodically alternating In... y2 Ga 1-y2 The superlattice structure formed by the N quantum well layer and the second GaN quantum barrier layer has a period number of 8; In y2 Ga 1-y2 The N-quantum well layer is an undoped InGaN layer with an In content of y² = 0.12. The second GaN quantum barrier layer is a Si-doped GaN layer with a Si doping concentration of 5.7 × 10⁻⁶. 17 / cm 3 In a single cycle, In y2 Ga 1-y2 The thickness of the N quantum well layer is 4 nm; the thickness of the second GaN quantum barrier layer is 10 nm. The first N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c1 = 4.7 × 10⁻⁶.19 / cm 3 The growth thickness is 3.5 μm; the second N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c² = 4.7 × 10⁻⁶. 19 / cm 3 The growth thickness is 3.5 μm; The electron dispersion layer is Si-doped Al x1 Ga 1-x1 N-layer and In y3 Ga 1-y3 The superlattice structure is formed by N alternating periodic layers with a period number of 15, in which Si-doped Al x1 Ga 1-x1 In the N-layer, the Al composition percentage is x1 = 0.50, and the Si doping concentration is 1.0 × 10⁻⁶. 18 / cm 3 In y3 Ga 1-y3 No intentional doping is performed in the N layer, and the In composition percentage is y3=0.05; Si-doped Al x1 Ga 1-x1 The N-layer has a growth thickness of 10 nm; In y3 Ga 1-y3 The N-layer has a growth thickness of 10 nm. The first electron blocking layer is Al. x3 Ga 1-x3 The N-layer has an Al component ratio of x3 = 0.45 and a growth thickness of 15 nm. The second electron blocking layer is Al. x4 Ga 1-x4 The N-layer has an Al component ratio of x4 = 0.45 and a growth thickness of 15 nm. Hole injection layer is Al x2 Ga 1-x2 N-layer and Mg-doped In y4 Ga 1-y4 A superlattice structure formed by N alternating periodic layers, with a period number of 10; wherein, Al x2 Ga 1-x2 No intentional doping is performed in the N layer; the Al component accounts for x2 = 0.6; Mg-doped In y4 Ga 1-y4 In the N-layer, the In composition percentage is y4 = 0.08, and the Mg doping concentration is 1 × 10⁻⁶. 19 / cm 3 Al x2 Ga 1-x2 The N-layer thickness was 1.9 nm; Mg-doped In y4 Ga 1-y4 The N-layer has a growth thickness of 1.9 nm; The p-type semiconductor layer is Mg-doped Al. a In b Ga 1-a-b N layers; wherein the Al component accounts for a = 0.15%, the In component accounts for b = 0.15%, and the Mg doping concentration is 4.4 × 10⁻⁶. 20 / cm 3 The thickness of the P-type semiconductor layer is 100 nm.

[0059] Its preparation method includes the following steps: (1) Provide a substrate; (2) Deposit a first N-type semiconductor layer on the substrate; (3) Deposit an electron dispersion layer on the first N-type semiconductor layer; (4) Deposit a second N-type semiconductor layer on the electron dispersion layer; (5) Deposit a first electron blocking layer on the second N-type semiconductor layer; (6) Deposit a first multi-quantum-well layer on the first electron blocking layer; (7) Deposit a second electron blocking layer on the first multiple quantum well layer; (8) Deposit a second multiple quantum well layer on the second electron blocking layer; (9) Deposit a hole injection layer on the second multiple quantum well layer; (10) Deposit a P-type semiconductor layer on the hole injection layer.

[0060] Example 2 This embodiment provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Embodiment 1, except that: The first N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c1 = 3.6 × 10⁻⁶. 18 / cm 3 The growth thickness is 6.8 μm; the second N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c² = 3.6 × 10⁻⁶. 18 / cm 3 The growth thickness is 0.5 μm; The electron dispersion layer has 2 periods, in which Si-doped Al x1 Ga 1-x1 In the N-layer, the Al composition percentage is x1 = 0.10, and the Si doping concentration is 2.0 × 10⁻⁶. 17 / cm 3 In y3 Ga 1-y3 The In composition percentage in the N layer is y3 = 0.003; Si-doped Al x1 Ga 1-x1 The N-layer has a growth thickness of 20 nm; In y3 Ga1-y3 The N-layer has a growth thickness of 16 nm. The first electron blocking layer is Al. x3 Ga 1-x3 The N-layer has an Al content of x3 = 0.03 and a growth thickness of 0.5 nm. The second electron blocking layer is Al. x4 Ga 1-x4 The N-layer has an Al content of x4 = 0.03 and a growth thickness of 0.5 nm. The number of cycles in the hole injection layer is 2; where Al x2 Ga 1-x2 The Al composition in the N layer is x2 = 0.16; Mg-doped In y4 Ga 1-y4 In the N-layer, the In composition percentage is y4 = 0.01, and the Mg doping concentration is 2 × 10⁻⁶. 18 / cm 3 Al x2 Ga 1-x2 The N-layer has a growth thickness of 3.6 nm; Mg-doped In y4 Ga 1-y4 The N-layer has a growth thickness of 3.6 nm.

[0061] The preparation method is the same as in Example 1.

[0062] Example 3 This embodiment provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Embodiment 1, except that: The first N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c1 = 5.8 × 10⁻⁶. 20 / cm 3 The growth thickness is 0.3 μm; the second N-type semiconductor layer is a Si-doped GaN layer with a Si doping concentration of c2 = 5.8 × 10⁻⁶. 20 / cm 3 The growth thickness was 6.8 μm; The electron dispersion layer has 30 periods, of which Si-doped Al x1 Ga 1-x1 In the N-layer, the Al composition percentage is x1 = 0.90, and the Si doping concentration is 8.8 × 10⁻⁶. 18 / cm 3 In y3 Ga 1-y3 The In composition percentage (y3) in the N layer is 0.10; Si-doped Al x1 Ga 1-x1 The N-layer has a growth thickness of 0.5 nm; In y3 Ga 1-y3 The N-layer has a growth thickness of 0.5 nm; The first electron blocking layer is Al. x3 Ga 1-x3 The N-layer has an Al content of x3 = 0.86 and a growth thickness of 25 nm. The second electron blocking layer is Al. x4 Ga 1-x4 The N-layer has an Al content of x4 = 0.86 and a growth thickness of 25 nm. The number of cycles in the hole injection layer is 18; among which, Al x2 Ga 1-x2 The Al component in the N layer accounts for x2 = 0.95; Mg-doped In y4 Ga 1-y4 In the N-layer, the In composition percentage is y4 = 0.16, and the Mg doping concentration is 5 × 10⁻⁶. 19 / cm 3 Al x2 Ga 1-x2 The N-layer has a growth thickness of 0.5 nm; Mg-doped In y4 Ga 1-y4 The N-layer has a growth thickness of 0.5 nm.

[0063] The preparation method is the same as in Example 1.

[0064] Example 4 This embodiment provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Embodiment 1, except that: The Si doping concentration in the first N-type semiconductor layer is c1 = 1 × 10⁻⁶ 20 / cm 3 .

[0065] The preparation method is the same as in Example 1.

[0066] Example 5 This embodiment provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in embodiment 4, except that: The thickness of the first electron blocking layer is 20 nm.

[0067] The preparation method is the same as in Example 1.

[0068] Comparative Example 1 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include an electron dispersion layer, i.e.: It includes a substrate, and a first N-type semiconductor layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked on the substrate.

[0069] The preparation method is the same as in Example 1.

[0070] Comparative Example 2 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include the first electron blocking layer, i.e.: It includes a substrate, and on the substrate, a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked.

[0071] The preparation method is the same as in Example 1.

[0072] Comparative Example 3 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include a second electron blocking layer, i.e.: It includes a substrate, and on the substrate, a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked.

[0073] The preparation method is the same as in Example 1.

[0074] Comparative Example 4 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include a hole injection layer, i.e.: It includes a substrate, and a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, and a P-type semiconductor layer are sequentially stacked on the substrate.

[0075] The preparation method is the same as in Example 1.

[0076] Comparative Example 5 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include the electron dispersion layer and the first electron blocking layer, i.e.: It includes a substrate, and a first N-type semiconductor layer, a second N-type semiconductor layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked on the substrate.

[0077] Comparative Example 6 This comparative example provides a dual-band light-emitting diode epitaxial wafer, which is basically the same as that in Example 1, except that it does not include the electron dispersion layer, the first electron blocking layer, and the second electron blocking layer, i.e.: It includes a substrate, and a first N-type semiconductor layer, a second N-type semiconductor layer, a first multiple quantum well layer, a second multiple quantum well layer, a hole injection layer and a P-type semiconductor layer are sequentially stacked on the substrate.

[0078] The epitaxial wafers prepared in Examples 1-5 and Comparative Examples 1-6 were used to fabricate 10mil×24mil white LED chips using the same chip process conditions and phosphor encapsulation process. 300 LED chips were extracted from each example, and the luminous efficiency and color rendering index (Ra) were tested at a current of 120mA. The improvement rate of luminous efficiency of Examples 1-5, Comparative Examples 1-2, and Comparative Examples 4-6 was calculated compared with the LED chip prepared in Comparative Example 3.

[0079] The specific test results are shown in Table 1.

[0080] Table 1 Performance test results of the examples and comparative examples

[0081] The results above show that by setting a first quantum well layer and a second quantum well layer between the second N-type semiconductor layer and the P-type semiconductor layer, and by setting four electron blocking layer structures in the epitaxial wafer of the dual-band light-emitting diode, a single LED chip can excite two bands of LED light source, reduce the use of phosphor in white LED backlight source, and improve luminous efficiency and color rendering index.

[0082] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A dual-band light-emitting diode epitaxial wafer, characterized in that, It includes a substrate, and on the substrate, a first N-type semiconductor layer, an electron dispersion layer, a second N-type semiconductor layer, a first electron blocking layer, a first multiple quantum well layer, a second electron blocking layer, a second multiple quantum well layer, a hole injection layer, and a P-type semiconductor layer are sequentially stacked. Wherein, the emission wavelength of the first quantum well layer is greater than the emission wavelength of the second quantum well layer; The electron dispersion layer is Si-doped Al. x1 Ga 1-x1 N-layer and In y3 Ga 1-y3 A superlattice structure formed by N layers of periodically alternating stacks; The first electron blocking layer includes Al x3 Ga 1-x3 N layers; The second electron blocking layer includes Al x4 Ga 1-x4 N layers; The hole injection layer is Al. x2 Ga 1-x2 N-layer and Mg-doped In y4 Ga 1-y4 A superlattice structure formed by the periodic alternation of N layers.

2. The dual-band light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The first multiple quantum well layer is a green light multiple quantum well layer, and the green light multiple quantum well layer is an In-type layer grown in a periodic alternating manner. y1 Ga 1-y1 The superlattice structure formed by the N quantum well layer and the first GaN quantum barrier layer has a period number of 2 to 10. The second multiple quantum well layer is a blue light multiple quantum well layer; the blue light multiple quantum well layer is an In-type layer grown in a periodic alternating pattern. y2 Ga 1-y2 The superlattice structure formed by the N quantum well layer and the second GaN quantum barrier layer has a period number of 2 to 12.

3. The dual-band light-emitting diode epitaxial wafer as described in claim 2, characterized in that, The In y1 Ga 1-y1 The N quantum well layer is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In composition is 0.22≤y1≤0.

28. The first GaN quantum barrier layer is a single-layer GaN structure doped with Si or a multilayer GaN structure doped with Si, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 ; The In y1 Ga 1-y1 The growth thickness of the N quantum well layer is 2nm~5nm; the growth thickness of the first GaN quantum barrier layer is 5nm~16nm; The In y2 Ga 1-y2 The N-quantum well layer is an undoped InGaN monolayer or InGaN multilayer structure, wherein the In content is 0.06 ≤ y² ≤ 0.19; the second GaN quantum barrier layer is a Si-doped GaN monolayer or Si-doped GaN multilayer structure, with a Si doping concentration of 1.6 × 10⁻⁶. 17 / cm 3 ~9.8×10 17 / cm 3 ; The In y2 Ga 1-y2 The growth thickness of the N quantum well layer is 2nm~5nm; the growth thickness of the second GaN quantum barrier layer is 5nm~16nm.

4. The dual-band light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The number of periods in the electron dispersion layer is 2 to 30; Wherein, the Si-doped Al x1 Ga 1-x1 In the N-layer, the Al composition percentage is 0.10 ≤ x1 ≤ 0.90, and the Si doping concentration is 2.0 × 10⁻⁶. 17 / cm 3 ~8.8×10 18 / cm 3 ; The In y3 Ga 1-y3 No intentional doping is performed in the N layer, and the In component ratio is 0.003≤y3≤0.10; The Si-doped Al x1 Ga 1-x1 The N-layer has a growth thickness of 0.2 nm to 20 nm; the In y3 Ga 1-y3 The growth thickness of the N layer ranges from 0.2 nm to 20 nm.

5. The dual-band light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The number of cycles in the hole injection layer is 2 to 18; Wherein, the Al x2 Ga 1-x2 No intentional doping is performed in the N layer, and the Al component percentage is 0.16 ≤ x2 < 1; the Mg-doped In y4 Ga 1-y4 In the N-layer, the In composition percentage is 0.01 ≤ y4 ≤ 0.16, and the Mg doping concentration is 2 × 10⁻⁶. 18 / cm 3 ~5×10 19 / cm 3 ; The Al x2 Ga 1-x2 The N-layer has a growth thickness of 0.2 nm to 3.6 nm; the Mg-doped In y4 Ga 1-y4 The growth thickness of the N layer ranges from 0.2 nm to 3.6 nm.

6. The dual-band light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The first electron blocking layer is Al x3 Ga 1-x3 N single-layer structure or Al x3 Ga 1-x3 The structure has N layers, and the second electron blocking layer is Al. x4 Ga 1-x4 N single-layer structure or Al x4 Ga 1-x4 Multi-layer structure; The growth thickness of the first electron blocking layer is greater than or equal to the growth thickness of the second electron blocking layer.

7. The dual-band light-emitting diode epitaxial wafer as described in claim 6, characterized in that, The thickness of the first electron blocking layer is 0.3 nm to 30 nm. The thickness of the second electron blocking layer is 0.3 nm to 30 nm. The proportion of Al component in the first electron blocking layer is 0.03≤x3≤0.86; the proportion of Al component in the second electron blocking layer is 0.03≤x4≤0.

86.

8. The dual-band light-emitting diode epitaxial wafer as described in claim 1, characterized in that, The first N-type semiconductor layer is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c1; the second N-type semiconductor layer is a Si-doped GaN monolayer structure or a Si-doped GaN multilayer structure, wherein the Si doping concentration is c2. It satisfies: c1≥c2.

9. The dual-band light-emitting diode epitaxial wafer as described in claim 8, characterized in that, The c1 satisfies: 3.6 × 10 18 / cm 3 ≤c1≤5.8×10 20 / cm 3 ; The c2 satisfies: 3.6 × 10 18 / cm 3 ≤c2≤5.8×10 20 / cm 3 ; The thickness of the first N-type semiconductor layer is 0.3 μm to 6.8 μm; the thickness of the second N-type semiconductor layer is 0.3 μm to 6.8 μm. The P-type semiconductor layer is Mg-doped Al. a In b Ga 1-a-b N layers; wherein the Al component has a proportion of 0 < a ≤ 0.3, the In component has a proportion of 0 < b ≤ 0.3, and the Mg doping concentration is 2.0 × 10⁻⁶. 19 / cm 3 ~6.8×10 21 / cm 3 The growth thickness of the P-type semiconductor layer is 5nm~500nm.

10. A method for fabricating a dual-band light-emitting diode epitaxial wafer as described in any one of claims 1-9, characterized in that, Includes the following steps: Provide a substrate; A first N-type semiconductor layer is deposited on the substrate; An electron dispersion layer is deposited on the first N-type semiconductor layer; A second N-type semiconductor layer is deposited on the electron dispersion layer; A first electron blocking layer is deposited on the second N-type semiconductor layer; A first multiple quantum well layer is deposited on the first electron blocking layer; A second electron blocking layer is deposited on the first multi-quantum-well layer; A second multiple quantum well layer is deposited on the second electron blocking layer; A hole injection layer is deposited on the second multiple quantum well layer; A P-type semiconductor layer is deposited on the hole injection layer; Wherein, the emission wavelength of the first quantum well layer is greater than the emission wavelength of the second quantum well layer; The electron dispersion layer is Si-doped Al. x1 Ga 1-x1 N-layer and In y3 Ga 1-y3 A superlattice structure formed by N layers of periodically alternating stacks; The first electron blocking layer includes Al x3 Ga 1-x3 N layers; The second electron blocking layer includes Al x4 Ga 1-x4 N layers; The hole injection layer is Al. x2 Ga 1-x2 N-layer and Mg-doped In y4 Ga 1-y4 A superlattice structure formed by the periodic alternation of N layers.

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