A semiconductor light emitting element

Abstract

The application provides a semiconductor light-emitting element, which comprises, from bottom to top, a substrate, an n-type semiconductor layer, a quantum well layer, an electron blocking layer and a p-type semiconductor layer, and the n-type semiconductor layer, the quantum well layer, the electron blocking layer and the p-type semiconductor layer have a dielectric constant gradient, a refractive index coefficient gradient and a forbidden band width gradient. The application designs the dielectric constant gradient, the refractive index coefficient gradient and the forbidden band width gradient between the n-type semiconductor layer, the quantum well layer, the electron blocking layer and the p-type semiconductor layer in the semiconductor light-emitting element, so that the reflection and refraction of light in the semiconductor light-emitting element are improved, the light-emitting angle of the outgoing light is increased, and the light-emitting angle is increased from 80-120 degrees to 120-200 degrees. Meanwhile, the outgoing path of the light can be changed, the light extraction efficiency is improved, and the light extraction efficiency is increased from 40-60% to 60-95%.

Description

Technical Field

[0001] This application relates to the field of semiconductor optoelectronic devices, and more particularly to a semiconductor light-emitting element. Background Technology

[0002] Semiconductor components, especially semiconductor light-emitting components, have a wide range of adjustable wavelengths, high luminous efficiency, energy saving and environmental protection, a long lifespan of over 100,000 hours, small size, multiple application scenarios, and strong design flexibility. As a result, they have gradually replaced incandescent and fluorescent lamps, becoming the light source for ordinary household lighting and are widely used in new scenarios, such as indoor high-resolution displays, outdoor displays, Mini-LED, Micro-LED, mobile phone TV backlights, backlighting, streetlights, car headlights, daytime running lights, car interior ambient lighting, flashlights, and other application areas.

[0003] Traditional nitride semiconductors are grown on sapphire substrates, resulting in large lattice and thermal mismatches, leading to high defect density and polarization effects, which reduce the luminous efficiency of semiconductor light-emitting devices. Simultaneously, the hole ionization efficiency of traditional nitride semiconductors is far lower than that of electron ionization, resulting in a hole concentration that is more than an order of magnitude lower than the electron concentration. Excess electrons overflow from the multiple quantum wells into the second conductivity type semiconductor, causing nonradiative recombination. The low hole ionization efficiency also makes it difficult for holes in the second conductivity type semiconductor to be effectively injected into the multiple quantum wells, leading to low hole injection efficiency and excessive electrons. The luminous efficiency of the quantum well is low; the nitride semiconductor structure has non-centrosymmetry, and strong spontaneous polarization will be generated along the c-axis direction. The piezoelectric polarization effect of lattice mismatch is superimposed to form an intrinsic polarization field; the intrinsic polarization field along the (001) direction causes a strong quantum confinement Stark effect in the multi-quantum well layer, causing band tilt and spatial separation of electron-hole wave functions, reducing the radiative recombination efficiency of electrons and holes; the refractive index, dielectric constant and other parameters of the semiconductor light-emitting element are greater than those of air, resulting in a smaller total reflection angle when the light emitted from the quantum well is emitted, and a lower light extraction efficiency. Summary of the Invention

[0004] To address one of the aforementioned technical problems, the present invention provides a semiconductor light-emitting element.

[0005] This invention provides a semiconductor light-emitting element, comprising a substrate, an n-type semiconductor layer, a quantum well layer, an electron blocking layer, and a p-type semiconductor layer arranged sequentially from bottom to top. The n-type semiconductor layer, the quantum well layer, the electron blocking layer, and the p-type semiconductor layer have gradients in dielectric constant, refractive index coefficient, and bandgap width.

[0006] Preferably, the quantum well layer includes a first sub-quantum well layer, a second sub-quantum well layer, and a third sub-quantum well layer. The first, second, and third sub-quantum well layers are all periodic structures composed of well layers and barrier layers. The number of periods in the first sub-quantum well layer is m: 30 ≥ m ≥ 1, the number of periods in the second sub-quantum well layer is n: 20 ≥ n ≥ 1, and the number of periods in the third sub-quantum well layer is r: 20 ≥ r ≥ 5.

[0007] Preferably, the dielectric constant gradient among the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 12≥d≥c≥b≥f≥a≥e≥8, where the dielectric constant of the n-type semiconductor is a, the dielectric constant of the first sub-quantum well layer is b, the dielectric constant of the second sub-quantum well layer is c, the dielectric constant of the third sub-quantum well layer is d, the dielectric constant of the electron blocking layer is e, and the dielectric constant of the p-type semiconductor is f.

[0008] Preferably, the refractive index coefficient gradient among the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 3.5≥j≥i≥h≥l≥g≥k≥1.5, where the refractive index coefficient of the n-type semiconductor is g, the refractive index coefficient of the first sub-quantum well layer is h, the refractive index coefficient of the second sub-quantum well layer is i, the refractive index coefficient of the third sub-quantum well layer is j, the refractive index coefficient of the electron blocking layer is k, and the refractive index coefficient of the p-type semiconductor is l.

[0009] Preferably, the bandgap coefficient gradient among the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 6.5eV≥y≥u≥z≥v≥w≥x≥0.5eV, where the bandgap of the n-type semiconductor is u, the bandgap of the first sub-quantum well layer is v, the bandgap of the second sub-quantum well layer is w, the bandgap of the third sub-quantum well layer is x, the bandgap of the electron blocking layer is y, and the bandgap of the p-type semiconductor is z.

[0010] Preferably, the well layer of the first sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the thickness of the well layer of the first sub-quantum well layer is 5 to 80 angstroms; the barrier layer of the first sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the first sub-quantum well layer is 10 to 500 angstroms.

[0011] Preferably, the well layer of the second sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the thickness of the well layer of the second sub-quantum well layer is 5 to 100 angstroms; the barrier layer of the second sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the second sub-quantum well layer is 10 to 300 angstroms.

[0012] Preferably, the well layer of the third sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the thickness of the well layer of the third sub-quantum well layer is 5 to 100 angstroms; the barrier layer of the third sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the third sub-quantum well layer is 10 to 200 angstroms.

[0013] Preferably, the n-type semiconductor, the electron blocking layer, and the p-type semiconductor include any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP; the thickness of the n-type semiconductor is 50–8000 nm; the thickness of the electron blocking layer is 5–9000 angstroms; and the thickness of the p-type semiconductor is 5–9000 angstroms.

[0014] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, or sapphire / SiN composite substrate. x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

[0015] The beneficial effects of this invention are as follows: By designing the dielectric constant gradient, refractive index gradient, and bandgap gradient among the n-type semiconductor layer, quantum well layer, electron blocking layer, and p-type semiconductor layer in the semiconductor light-emitting element, this invention enhances the reflection and refraction of light in the semiconductor light-emitting element, increasing the emission angle of the emitted light from the existing 80° to 120° to 120° to 200°. Simultaneously, it can also change the light emission path, improving the light extraction efficiency from the existing 40% to 60% to 60% to 95%. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of the semiconductor light-emitting element according to Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the semiconductor light-emitting element according to Embodiment 2 of the present invention;

[0019] Figure 3 This is a SIMS secondary ion mass spectrum of the semiconductor light-emitting element described in Embodiment 2 of the present invention;

[0020] Figure 4 This is a SIMS secondary ion mass spectrum of a partial structure of the semiconductor light-emitting element described in Embodiment 2 of the present invention;

[0021] Figure 5 This is a transmission electron microscope (TEM) image of the first sub-quantum well layer of the semiconductor light-emitting element in Embodiment 2 of the present invention;

[0022] Figure 6 This is a transmission electron microscope (TEM) image of the second sub-quantum well layer of the semiconductor light-emitting element in Embodiment 2 of the present invention;

[0023] Figure 7 This is a transmission electron microscope (TEM) image of the third sub-quantum well layer of the semiconductor light-emitting element in Embodiment 2 of the present invention;

[0024] Figure 8 This is a transmission electron microscope (TEM) image of the electron blocking layer of the semiconductor light-emitting element according to Embodiment 2 of the present invention.

[0025] Figure label:

[0026] 100. Substrate; 101. n-type semiconductor layer; 102. Quantum well layer; 103. Electron blocking layer; 104. p-type semiconductor layer;

[0027] 102a, First sub-quantum well layer; 102b, Second sub-quantum well layer; 102c, Third sub-quantum well layer. Detailed Implementation

[0028] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment proposes a semiconductor light-emitting element, including a substrate 100, an n-type semiconductor layer 101, a quantum well layer 102, an electron blocking layer 103 and a p-type semiconductor layer 104 arranged sequentially from bottom to top.

[0031] Specifically, in this embodiment, the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 all possess dielectric constant, refractive index constant, and bandgap width parameters. Furthermore, the dielectric constant, refractive index constant, and bandgap width can affect the emission angle of the emitted light and the light extraction efficiency.

[0032] The dielectric constant is a physical quantity that represents the energy generated when a portion of the charge in a crystalline material is held by an electric field. It is linearly related to the strength of the electric field and is the dielectric constant that determines the change in potential inside an object when a bias current is generated in an electric field.

[0033] The refractive index is the ratio of the speed of light in a vacuum to the speed of light in the medium. The higher the refractive index of a material, the stronger its ability to refract incident light.

[0034] The bandgap refers to the energy difference between the bottom of the conduction band and the top of the valence band in a semiconductor light-emitting device. It reflects the minimum energy required for an electron to transition from the valence band to the conduction band. Generally speaking, the smaller the bandgap, the better the conductivity of the semiconductor light-emitting device.

[0035] Based on the characteristics of dielectric constant, refractive index constant, and bandgap, this embodiment designs the dielectric constant gradient, refractive index coefficient gradient, and bandgap gradient between the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104, thereby achieving the purpose of changing the emission angle of the emitted light and the light extraction efficiency.

[0036] Specifically, in this embodiment, the dielectric constant gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as follows: dielectric constant of quantum well layer 102 ≥ dielectric constant of p-type semiconductor layer 104 ≥ dielectric constant of n-type semiconductor layer 101 ≥ dielectric constant of electron blocking layer 103, and the dielectric constants of n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 are all between 8 and 12.

[0037] The refractive index constant gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as follows: the refractive index constant of quantum well layer 102 ≥ the refractive index constant of p-type semiconductor layer 104 ≥ the refractive index constant of n-type semiconductor layer 101 ≥ the refractive index constant of electron blocking layer 103, and the refractive index constants of n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 are all between 1.5 and 3.5.

[0038] The bandgap gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as follows: the bandgap of electron blocking layer 103 ≥ the bandgap of n-type semiconductor layer 101 ≥ the bandgap of p-type semiconductor layer 104 ≥ the bandgap of quantum well layer 102, and the bandgap of n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 are all between 0.5 eV and 6.5 eV.

[0039] This embodiment improves light reflection and refraction within the semiconductor light-emitting element by designing the dielectric constant gradient, refractive index gradient, and bandgap gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104. This increases the emission angle of the emitted light from the existing 80°-120° to 120°-200°. Simultaneously, it alters the light emission path, improving light extraction efficiency from the existing 40%-60% to 60%-95%.

[0040] Furthermore, in this embodiment, the n-type semiconductor, electron blocking layer 103, and p-type semiconductor include any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP. The thickness of the n-type semiconductor is 50–8000 nm. The thickness of the electron blocking layer 103 is 5–9000 angstroms. The thickness of the p-type semiconductor is 5–9000 angstroms. The substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, and sapphire / SiN composite substrate. x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

[0041] Example 2

[0042] like Figures 2 to 8 As shown, this embodiment proposes a semiconductor light-emitting element, including a substrate 100, an n-type semiconductor layer 101, a quantum well layer 102, an electron blocking layer 103 and a p-type semiconductor layer 104 arranged sequentially from bottom to top.

[0043] Specifically, in this embodiment, the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 all possess dielectric constant, refractive index constant, and bandgap width parameters. Furthermore, the dielectric constant, refractive index constant, and bandgap width can affect the emission angle of the emitted light and the light extraction efficiency. The specific meanings of the dielectric constant, refractive index constant, and bandgap width can be found in Embodiment 1, and will not be repeated in this embodiment.

[0044] In order to further achieve the purpose of changing the emission angle and light extraction efficiency of the emitted light, this embodiment designs the gradient of dielectric constant, gradient of refractive index coefficient and gradient of bandgap between n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103 and p-type semiconductor layer 104 based on the characteristics of dielectric constant, refractive index constant and bandgap width. The quantum well layer 102 is designed as a three-layer periodic structure.

[0045] Specifically, in this embodiment, the quantum well layer 102 includes a first sub-quantum well layer 102a, a second sub-quantum well layer 102b, and a third sub-quantum well layer 102c, and each of these layers is a periodic structure composed of well layers and barrier layers. The period number of the first sub-quantum well layer 102a is m: 30 ≥ m ≥ 1, the period number of the second sub-quantum well layer 102b is n: 20 ≥ n ≥ 1, and the period number of the third sub-quantum well layer 102c is r: 20 ≥ r ≥ 5.

[0046] In this embodiment, the third sub-quantum well is the active layer 102c, which restricts radiative recombination of electrons and holes within the quantum well layer 102. The first sub-quantum well layer 102a and the second sub-quantum well layer 102b can adjust the lattice mismatch stress between the third sub-quantum well layer 102c (the light-emitting layer) and the n-type semiconductor layer 101, thereby releasing stress and controlling the piezoelectric polarization effect. Simultaneously, the first, second, and third sub-quantum well layers 102a, 102b, and 102c, as shallow quantum wells, act as electron spreading layers, enhancing current spreading. Furthermore, by designing the dielectric constant gradient, refractive index gradient, and bandgap gradient of the first, second, and third sub-quantum well layers 102a, 102b, and 102c, the size and density of V-type dislocations can be adjusted, improving the hole injection efficiency from the V-type dislocation sidewalls and thus enhancing quantum efficiency.

[0047] Based on this, in this embodiment, the dielectric constant gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as: 1 / 2 ≥ d ≥ c ≥ b ≥ f ≥ a ≥ e ≥ 8. Wherein, the dielectric constant of the n-type semiconductor is a, the dielectric constant of the first sub-quantum well layer 102a is b, the dielectric constant of the second sub-quantum well layer 102b is c, the dielectric constant of the third sub-quantum well layer 102c is d, the dielectric constant of the electron blocking layer 103 is e, and the dielectric constant of the p-type semiconductor is f.

[0048] The refractive index constant gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as: 3.5 ≥ j ≥ i ≥ h ≥ l ≥ g ≥ k ≥ 1.5. Wherein, the refractive index coefficient of the n-type semiconductor is g, the refractive index coefficient of the first sub-quantum well layer 102a is h, the refractive index coefficient of the second sub-quantum well layer 102b is i, the refractive index coefficient of the third sub-quantum well layer 102c is j, the refractive index coefficient of the electron blocking layer 103 is k, and the refractive index coefficient of the p-type semiconductor is l.

[0049] The bandgap gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104 is expressed as: 6.5 eV ≥ y ≥ u ≥ z ≥ v ≥ w ≥ x ≥ 0.5 eV. Wherein, the bandgap of the n-type semiconductor is u, the bandgap of the first sub-quantum well layer 102a is v, the bandgap of the second sub-quantum well layer 102b is w, the bandgap of the third sub-quantum well layer 102c is x, the bandgap of the electron blocking layer 103 is y, and the bandgap of the p-type semiconductor is z.

[0050] This embodiment improves light reflection and refraction within the semiconductor light-emitting element by designing the dielectric constant gradient, refractive index gradient, and bandgap gradient among the n-type semiconductor layer 101, quantum well layer 102, electron blocking layer 103, and p-type semiconductor layer 104. This increases the emission angle of the emitted light from the existing 80°-120° to 120°-200°. Simultaneously, it alters the light emission path, improving light extraction efficiency from the existing 40%-60% to 60%-95%.

[0051] Furthermore, in this embodiment, the well layer of the first sub-quantum well layer 102a is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN. The thickness of the well layer of the first sub-quantum well layer 102a is 5–80 angstroms. The barrier layer of the first sub-quantum well layer 102a is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN. The thickness of the barrier layer of the first sub-quantum well layer 102a is 10–500 angstroms.

[0052] The well layer of the second sub-quantum well layer 102b is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN. The thickness of the well layer of the second sub-quantum well layer 102b is 5–100 angstroms. The barrier layer of the second sub-quantum well layer 102b is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN. The thickness of the barrier layer of the second sub-quantum well layer 102b is 10–300 angstroms.

[0053] The well layer of the third sub-quantum well layer 102c is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN. The thickness of the well layer of the third sub-quantum well layer 102c is 5–100 angstroms. The barrier layer of the third sub-quantum well layer 102c is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN. The thickness of the barrier layer of the third sub-quantum well layer 102c is 10–200 angstroms.

[0054] Furthermore, in this embodiment, the n-type semiconductor, electron blocking layer 103, and p-type semiconductor include any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP. The thickness of the n-type semiconductor is 50–8000 nm. The thickness of the electron blocking layer 103 is 5–9000 angstroms. The thickness of the p-type semiconductor is 5–9000 angstroms. The substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, and sapphire / SiN composite substrate. x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

[0055] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A semiconductor light-emitting element, characterized in that, It includes a substrate, an n-type semiconductor layer, a quantum well layer, an electron blocking layer, and a p-type semiconductor layer arranged sequentially from bottom to top. The n-type semiconductor layer, the quantum well layer, the electron blocking layer, and the p-type semiconductor layer have gradients in dielectric constant, refractive index coefficient, and bandgap width. The quantum well layer includes a first sub-quantum well layer, a second sub-quantum well layer, and a third sub-quantum well layer. Each of these layers is a periodic structure composed of a well layer and a barrier layer. The first sub-quantum well layer has a period number m: 30 ≥ m ≥ 1, a well layer thickness of 5–80 Å, and a barrier layer thickness of 10–500 Å. The second sub-quantum well layer has a period number n: 20 ≥ n ≥ 1, a well layer thickness of 5–100 Å, and a barrier layer thickness of 10–300 Å. The third sub-quantum well layer has a period number r: 20 ≥ r ≥ 5, a well layer thickness of 5–100 Å, and a barrier layer thickness of 10–200 Å. The dielectric constant gradient between the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 12≥d≥c≥b≥f≥a≥e≥8, where the dielectric constant of the n-type semiconductor is a, the dielectric constant of the first sub-quantum well layer is b, the dielectric constant of the second sub-quantum well layer is c, the dielectric constant of the third sub-quantum well layer is d, the dielectric constant of the electron blocking layer is e, and the dielectric constant of the p-type semiconductor is f. The refractive index gradient among the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 3.5≥j≥i≥h≥l≥g≥k≥1.5, where the refractive index coefficient of the n-type semiconductor is g, the refractive index coefficient of the first sub-quantum well layer is h, the refractive index coefficient of the second sub-quantum well layer is i, the refractive index coefficient of the third sub-quantum well layer is j, the refractive index coefficient of the electron blocking layer is k, and the refractive index coefficient of the p-type semiconductor is l. The bandgap coefficient gradient between the n-type semiconductor layer, the first sub-quantum well layer, the second sub-quantum well layer, the third sub-quantum well layer, the electron blocking layer, and the p-type semiconductor layer is: 6.5eV≥y≥u≥z≥v≥w≥x≥0.5eV, where u is the bandgap of the n-type semiconductor, v is the bandgap of the first sub-quantum well layer, w is the bandgap of the second sub-quantum well layer, x is the bandgap of the third sub-quantum well layer, y is the bandgap of the electron blocking layer, and z is the bandgap of the p-type semiconductor.

2. The semiconductor light-emitting element according to claim 1, characterized in that, The well layer of the first sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN; the barrier layer of the first sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN.

3. The semiconductor light-emitting element according to claim 1, characterized in that, The well layer of the second sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN; the barrier layer of the second sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN.

4. The semiconductor light-emitting element according to claim 1, characterized in that, The well layer of the third sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN; the barrier layer of the third sub-quantum well layer is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN.

5. The semiconductor light-emitting element according to claim 1, characterized in that, The n-type semiconductor, electron blocking layer, and p-type semiconductor include any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP; the thickness of the n-type semiconductor is 50~8000 nm; the thickness of the electron blocking layer is 5~9000 angstroms; and the thickness of the p-type semiconductor is 5~9000 angstroms.

6. The semiconductor light-emitting element according to claim 1, characterized in that, The substrates include sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrates, sapphire / AlN composite substrates, and sapphire / SiN composite substrates. x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

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