Semiconductor light-emitting element

Abstract

Provided is a semiconductor light-emitting element. The semiconductor light-emitting element comprises: a substrate, an electron-type semiconductor, quantum wells, an electron-blocking layer and a hole-type semiconductor, which are sequentially stacked, wherein respective optical parameters of a first quantum well, a second quantum well and a third quantum well among the quantum wells are distributed in a gradient manner in at least one direction; each quantum well comprises a periodic structure composed of a well layer and a barrier layer; a thermal expansion coefficient of the well layer is less than or equal to a thermal expansion coefficient of the barrier layer; an elastic coefficient of the well layer is less than or equal to an elastic coefficient of the barrier layer; a lattice constant of the well layer is greater than or equal to a lattice constant of the barrier layer; and a spontaneous polarization coefficient of the well layer is less than or equal to a spontaneous polarization coefficient of the barrier layer. By designing optical parameters of quantum wells to be distributed in a gradient manner in at least one direction, the reflection and refraction of light can be improved, and the light emission angle of emergent light is increased, thereby improving light extraction efficiency. Moreover, by designing parameter differences of the quantum wells, the thermal mismatch and lattice mismatch of the quantum wells can be reduced.

Description

A semiconductor light-emitting element Technical Field

[0001] This specification relates to the technical field of semiconductor optoelectronic devices, specifically a semiconductor light-emitting element. Background Art

[0002] Semiconductor light-emitting elements, especially semiconductor light-emitting elements, have a wide range of adjustable wavelengths, high luminous efficiency, energy saving and environmental protection, a long life of more than 100,000 hours, small size, multiple application scenarios, and strong designability. They have gradually replaced incandescent lamps and fluorescent lamps as light sources for ordinary household lighting, and are widely used in new scenarios, such as indoor high-resolution display screens, outdoor display screens, Mini-LED, Micro-LED, mobile TV backlight, backlight lighting, street lights, car headlights, daytime running lights, interior atmosphere lights, flashlights and other application fields.

[0003] Conventional nitride semiconductors are grown on commonly used substrates, which can easily lead to large lattice mismatch and thermal mismatch, resulting in higher defect density and polarization effect, reducing the luminous efficiency of semiconductor light-emitting elements. At the same time, the hole ionization efficiency of conventional nitride semiconductors is much lower than the electron ionization efficiency, resulting in a hole concentration that is more than one order of magnitude lower than the electron concentration. Excess electrons will overflow from the multi-quantum well to the second conductive semiconductor to produce non-radiative recombination. The low hole ionization efficiency will make it difficult for holes in the second conductive semiconductor to be effectively injected into the multi-quantum well, resulting in low luminous efficiency of the multi-quantum well. ; Furthermore, the nitride semiconductor structure has non-central symmetry, and will produce strong spontaneous polarization along the c-axis direction, superimposed with the piezoelectric polarization effect of lattice mismatch to form an intrinsic polarization field; this intrinsic polarization field along the direction of the crystal c-axis causes the multi-quantum well layer to produce a strong quantum-confined Stark effect, causing energy 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 small total reflection angle of the light emitted by the quantum well when it is emitted, and a low light extraction efficiency.

[0004] Therefore, it is desirable to provide a semiconductor light emitting element to improve the light emitting efficiency and quality of the semiconductor light emitting element.

[0005] Summary of the Invention

[0006] One embodiment of the present specification provides a semiconductor light-emitting element. The semiconductor light-emitting element comprises: a substrate, an electron-type semiconductor, a quantum well, an electron blocking layer, and a hole-type semiconductor stacked in sequence; the quantum well comprises a first quantum well, a second quantum well, and a third quantum well; the first quantum well, the second quantum well, and the third quantum well have different dielectric constants, refractive indices, band gaps, and electron effective masses, such that the dielectric constant, refractive index, band gap, and electron effective mass of the semiconductor light-emitting element are gradient-distributed in at least one direction; the quantum well comprises a periodic structure consisting of a well layer and a barrier layer, the number of periods of the periodic structure being 1 to 50; the thermal expansion coefficient of the well layer is less than or equal to the thermal expansion coefficient of the barrier layer; the elastic coefficient of the well layer is less than or equal to the elastic coefficient of the barrier layer; the lattice constant of the well layer is greater than or equal to the lattice constant of the barrier layer; and the spontaneous polarization coefficient of the well layer is less than or equal to the spontaneous polarization coefficient of the barrier layer.

[0007] In some embodiments, the dielectric constant of the electron-type semiconductor is a, the dielectric constant of the well layer of the first quantum well is b, the dielectric constant of the well layer of the second quantum well is c, the dielectric constant of the well layer of the third quantum well is d, the dielectric constant of the electron blocking layer is e, the dielectric constant of the hole-type semiconductor is f, and the dielectric constant of the semiconductor light-emitting element includes the following gradient relationship: 12≥d≥c≥b≥f≥a≥e≥8.

[0008] In some embodiments, the refractive index coefficient of the electron-type semiconductor is g, the refractive index coefficient of the well layer of the first quantum well is h, the refractive index coefficient of the well layer of the second quantum well is i, the refractive index coefficient of the well layer of the third quantum well is j, the refractive index coefficient of the electron blocking layer is k, the refractive index coefficient of the hole-type semiconductor is l, and the refractive index coefficient of the semiconductor light-emitting element includes the following gradient relationship: 3.5≥j≥i≥h≥l≥g≥k≥1.5.

[0009] In some embodiments, the band gap width of the electron-type semiconductor is u, the band gap width of the well layer of the first quantum well is v, the band gap width of the well layer of the second quantum well is w, the band gap width of the well layer of the third quantum well is x, the band gap width of the electron blocking layer is y, the band gap width of the hole-type semiconductor is z, and the band gap width of the semiconductor light-emitting element includes the following gradient relationship: 6.5eV≥y≥u≥z≥v≥w≥x≥0.5eV.

[0010] In some embodiments, the electron effective mass of the electron-type semiconductor is o, the electron effective mass of the well layer of the first quantum well is p, the electron effective mass of the well layer of the second quantum well is q, the electron effective mass of the well layer of the third quantum well is r, the electron effective mass of the electron blocking layer is s, the electron effective mass of the hole-type semiconductor is t, and the electron effective mass of the semiconductor light-emitting element includes the following gradient relationship: 10m e ≥s≥o≥t≥p≥q≥r≥0.01m e .

[0011] In some embodiments, the electron blocking layer includes a Mg doping concentration distribution, an Al element concentration distribution, an In element concentration distribution, a Si doping concentration distribution, a C element concentration distribution, an H element concentration distribution, and an O element concentration distribution in at least one direction; the Mg doping concentration distribution of the electron blocking layer is parabolic, and the peak position of the Mg doping concentration distribution is downward in the direction of the quantum well interface, and the angle of decrease of the Mg doping concentration distribution is φ, and the angle range of φ is 30°≤φ≤90°; the Si doping concentration distribution of the electron blocking layer is W-shaped, and the Si doping concentration distribution is downward in the direction of the quantum well, and the angle range of θ is 20°≤θ≤85°; the Al element concentration distribution of the electron blocking layer is M-shaped, and the peak position of the Al element concentration distribution is downward in the direction of the quantum well, and the Al element concentration distribution is The decreasing angle of α is α, and the angle range of α is 10°≤α≤80°; the In element concentration distribution of the electron blocking layer is parabolic, and the peak position of the In element concentration distribution shows a downward trend toward the quantum well, and the decreasing angle of the In element concentration distribution is ρ, and the angle range of ρ is 15°≤ρ≤85°; the peak position of the H element concentration distribution of the electron blocking layer shows a downward trend toward the quantum well, and the decreasing angle of the H element concentration distribution is ε, and the angle range of ε is 15°≤ε≤85°; the peak position of the C element concentration distribution of the electron blocking layer shows a downward trend toward the quantum well, and the decreasing angle of the C element concentration distribution is δ, and the angle range of δ is 10°≤δ≤80°; the peak position of the O element concentration distribution of the electron blocking layer shows a downward trend toward the quantum well, and the decreasing angle of the O element concentration distribution is ψ, and the angle range of ψ is 25°≤ψ≤85°.

[0012] In some embodiments, the descending angle of the electron blocking layer includes the following relationship: 10°≤α≤δ≤ρ≤ε≤θ≤ψ≤φ≤85°.

[0013] In some embodiments, the electron blocking layer further includes an electron effective mass distribution in a V-type distribution or an M-type distribution; the electron blocking layer includes a piezoelectric polarization coefficient distribution in an M-type distribution; the electron blocking layer includes an inverted V-shaped dielectric constant distribution; the electron blocking layer includes an Al / O element concentration ratio distribution in an M-type distribution and an In / O element concentration ratio distribution in an N-type distribution; the electron blocking layer includes a Mg / O element concentration ratio distribution in a parabolic distribution.

[0014] In some embodiments, the well layer of the first quantum well includes any one of InGaN, GaN, AlGaN, AlInGaN, and AlInN, or any combination thereof, and the thickness of the well layer of the first quantum well is 5 angstroms to 80 angstroms; the barrier layer of the first quantum well includes any one of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, or any combination thereof, and the thickness of the barrier layer of the first quantum well is 10 to 500 angstroms; the Al element concentration distribution of the first quantum well shows a downward trend toward the electronic semiconductor, and the downward angle of the Al element concentration distribution is ν, and the angle range of ν is 15°≤ν≤75°; the C / O element concentration ratio distribution of the first quantum well is V-shaped distribution, the C / O element concentration ratio distribution shows a downward trend toward the hole-type semiconductor, the decreasing angle of the C / O element concentration ratio distribution is ω, and the angle range of ω is 20°≤ω≤80°; the well layer of the second quantum well includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the well layer thickness of the second quantum well is 5 angstroms to 100 angstroms; the barrier layer of the second quantum well includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the barrier layer thickness of the second quantum well is 10 angstroms to 300 angstroms; the Al element concentration distribution of the second quantum well is toward the electron-type semiconductor The conductor direction is downward, the Al element concentration distribution is at a decreasing angle of μ, and the angle range of μ is 20°≤μ≤80°; the C / O element concentration ratio distribution of the second quantum well is L-shaped, the C / O element concentration ratio distribution is downward in the direction of the hole-type semiconductor, the C / O element concentration ratio distribution is at a decreasing angle of γ, and the angle range of γ is 25°≤γ≤85°; the well layer of the third quantum well includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the well layer thickness of the third quantum well is 5 angstroms to 150 angstroms; the barrier layer of the third quantum well is InGaN, GaN, AlGaN, AlInGaN, and AlIn N, AlN, any one or any combination thereof, the barrier layer thickness of the third quantum well is 10 angstroms to 200 angstroms; the Al element concentration distribution of the third quantum well shows a downward trend toward the electronic semiconductor, the downward angle of the Al element concentration distribution is λ, and the angle range of λ is 30°≤λ≤90°; the C / O element concentration ratio distribution of the third quantum well shows a downward trend toward the electronic semiconductor, the downward angle of the C / O element concentration ratio distribution is β, and the angle range of β is 10°≤β≤70°; the H / O element concentration ratio distribution of the third quantum well shows a downward trend toward the electronic semiconductor, the downward angle of the H / O element concentration ratio distribution is κ, and the angle range of κ is 20°≤κ≤80°;The Al / O element drop angle, the C / O element concentration ratio distribution drop angle, and the H / O element concentration ratio distribution drop angle of the first quantum well, the second quantum well, and the third quantum well include the following relationship: 10°≤β≤ν≤μ≤ω≤κ≤γ≤λ≤90°.

[0015] In some embodiments, electron-type semiconductors and hole-type semiconductors include AlGaN, GaN, InGaN, InN, AlInN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC , Ga2O3, BN or any combination thereof; the thickness of the electron-type semiconductor is 5 angstroms to 80,000 angstroms; the thickness of the hole-type semiconductor is 5 angstroms to 9,000 angstroms; the substrate includes any one or more combinations of sapphire, silicon, Ge, SiC, AlN, InAs, GaSb, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiNx, magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] This specification will be further described in the form of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting, and in these embodiments, like numbers represent like structures, wherein:

[0017] FIG1 is a schematic structural diagram of a semiconductor light-emitting element provided in an embodiment of this specification;

[0018] FIG2 is a SIMS secondary ion mass spectrum of the structure of a semiconductor light-emitting element provided in an embodiment of this specification;

[0019] FIG3 is a SIMS secondary ion mass spectrum of a local structure of a quantum well of a semiconductor light-emitting element provided in an embodiment of this specification;

[0020] FIG4 is a SIMS secondary ion mass spectrum of a local structure of an electron blocking layer of a semiconductor light-emitting element provided in an embodiment of this specification;

[0021] FIG5 is a transmission electron microscope (TEM) image of a first quantum well of a semiconductor light-emitting element provided in an embodiment of this specification;

[0022] FIG6 is a transmission electron microscope (TEM) image of a second quantum well of a semiconductor light-emitting element provided in an embodiment of this specification;

[0023] FIG7 is a transmission electron microscope (TEM) image of a third quantum well of a semiconductor light-emitting element provided in an embodiment of this specification;

[0024] FIG8 is a transmission electron microscope (TEM) image of an electron blocking layer of a semiconductor light-emitting element provided in an embodiment of this specification;

[0025] Reference numerals: 100: substrate, 101: electron-type semiconductor, 102: quantum well, 102a: first quantum well, 102b: second quantum well, 102c: third quantum well, 103: electron blocking layer, 104: hole-type semiconductor. DETAILED DESCRIPTION

[0026] To more clearly illustrate the technical solutions of the embodiments of this specification, the following briefly describes the drawings required for describing the embodiments. Obviously, the drawings described below are merely examples or embodiments of this specification. Those skilled in the art can apply this specification to other similar scenarios based on these drawings without inventive effort. Unless otherwise apparent from the context or otherwise noted, the same reference numerals in the figures represent the same structure or operation.

[0027] It should be understood that the terms "system," "device," "unit," and / or "module" used herein are a method for distinguishing different components, elements, parts, portions, or assemblies at different levels. However, if other terms can achieve the same purpose, the terms may be replaced by other expressions.

[0028] As used in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not refer to the singular but also include the plural. Generally speaking, the terms "comprises" and "include" only indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list. A method or apparatus may also include other steps or elements.

[0029] Flowcharts are used throughout this specification to illustrate the operations performed by systems according to embodiments of this specification. It should be understood that preceding or following operations do not necessarily need to be performed in exact order. Instead, the steps may be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0030] Regarding how to emit visible light, the existing technology uses semiconductor light-emitting elements to emit light. Among them, it is proposed that the semiconductor light-emitting element may include an electron-type semiconductor, a quantum well, an electron blocking layer, and a hole-type semiconductor. The semiconductor light-emitting element can control the electron-type semiconductor and the hole-type semiconductor under the action of an external electric field to provide electrons and holes and recombine in the quantum well. Through the recombination of electrons and holes, photons are generated and visible light is emitted. However, the hole ionization efficiency of this semiconductor light-emitting element is much lower than the electron ionization efficiency, resulting in too few holes and too many electrons injected into the multi-quantum well, resulting in low luminescence efficiency of the multi-quantum well.

[0031] This specification describes a semiconductor light-emitting element, which can improve the reflection and refraction of light and increase the luminous angle of the emitted light by designing the dielectric constant, refractive index, bandgap width and electron effective mass to be gradiently distributed in at least one direction. For example, the luminous angle can be increased from at least 80° to 120° to 120° to 200°, and can change the light emission path to improve the light extraction efficiency, such as at least increasing the light extraction efficiency from 40% to 60% to 60% to 95%.

[0032] It should be understood that the application scenarios of the semiconductor light-emitting elements of the present application are merely some examples or embodiments of the present application. For ordinary technicians in this field, without paying any creative work, they can also apply the present application to other similar scenarios based on these drawings.

[0033] The semiconductor light emitting element according to the embodiments of the present application will be described in detail below with reference to Figures 1 to 8. It should be noted that the following embodiments are only used to explain the present application and do not constitute a limitation of the present application.

[0034] Figure 1 is a schematic diagram of the structure of a semiconductor light-emitting element according to some embodiments of this specification. In some embodiments, as shown in Figure 1, the semiconductor light-emitting element may include a substrate 100, an electron-type semiconductor 101, a quantum well 102, an electron blocking layer 103, and a hole-type semiconductor 104. The substrate 100, electron-type semiconductor 101, quantum well 102, electron blocking layer 103, and hole-type semiconductor 104 may be stacked in sequence.

[0035] The substrate 100 refers to a component used to support other components in the semiconductor light emitting element 100 , such as the electronic semiconductor 101 , the quantum well 102 , and the like.

[0036] In some embodiments, the substrate 100 can be made of a material that meets preset substrate conditions. These preset substrate conditions can include the lattice mismatch and thermal mismatch of the substrate 100 material being less than or equal to a preset mismatch threshold. The preset mismatch threshold can be determined based on empirical experience and historical semiconductor material data. In other words, the substrate 100 can be made of a material with minimal lattice mismatch and thermal mismatch to reduce the defect density and polarization effects of the semiconductor light-emitting element 100. For more information on lattice mismatch and thermal mismatch, please refer to the relevant description below.

[0037] In some embodiments, the substrate 100 may be any one or more of sapphire, silicon, Ge, SiC, AlN, InAs, GaSb, GaN, GaAs, InP, a sapphire / SiO2 composite substrate, a sapphire / AlN composite substrate, a sapphire / SiNx, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and a LiGaO2 composite substrate.

[0038] The electron-type semiconductor 101, also known as an N-type semiconductor, refers to an impurity semiconductor in which the free electron concentration is greater than the hole concentration. The free electrons are primarily provided by impurity atoms in the electron-type semiconductor 101, while holes can be formed by thermal excitation. In some embodiments, the concentration of impurities doped into the electron-type semiconductor 101 can be positively correlated with the conductivity of the free electrons. For example, the more impurities doped into the electron-type semiconductor 101, the higher the concentration of free electrons and the stronger the conductivity of the free electrons.

[0039] In some embodiments, the electronic semiconductor 101 can be stacked on top of the substrate 100. In some embodiments, the electronic semiconductor 101 can provide electrons under the action of an external electric field for subsequent recombination with holes. For example, as shown in Figure 1, the electrons generated by the electronic semiconductor 101 can move along a first direction (direction x as shown in Figure 1) to the quantum well and recombine with the holes. For more information about quantum wells and holes, please refer to the relevant description below.

[0040] The quantum well 102 is a region that exhibits two-dimensional characteristics due to the movement of electrons. In some embodiments, the quantum well 102 can be disposed between the electron-type semiconductor 101 and the hole-type semiconductor 104 described below, so that electrons and holes can be collected to generate light.

[0041] In some embodiments, the quantum well 102 may include a periodic structure consisting of well layers and barrier layers, with the periodic structure having a period number of 1 to 50. The quantum well 102 may be arranged in a periodic manner with well layers and barrier layers alternately stacked. Under the action of an external electric field, electrons in the quantum well 102 transition from a low-energy band material (e.g., a barrier layer) to a high-energy band material (e.g., a well layer), releasing energy at the same time. This energy is converted into photons, thereby generating laser light.

[0042] In some embodiments, there may be differences in parameters between the well layer and the barrier layer, such as parameters such as thermal expansion coefficient, elastic coefficient, lattice constant and spontaneous polarization coefficient. The parameter difference between the well layer and the barrier layer can make at least a part of the structure in the quantum well 102 (such as the well layer and the barrier layer) adaptable to the substrate 100, thereby reducing the possibility of lattice mismatch and thermal mismatch in the semiconductor light-emitting element. Among them, lattice mismatch refers to the phenomenon that the distance and angle between atoms in the crystal do not meet the requirements of an ideal crystal. Thermal mismatch refers to the mismatch phenomenon caused by different thermal expansion coefficients when the material changes in temperature.

[0043] In some embodiments, the thermal expansion coefficient of the well layer may be less than or equal to the thermal expansion coefficient of the barrier layer; the elastic coefficient of the well layer may be less than or equal to the elastic coefficient of the barrier layer; the lattice constant of the well layer may be greater than or equal to the lattice constant of the barrier layer; and the spontaneous polarization coefficient of the well layer may be less than or equal to the spontaneous polarization coefficient of the barrier layer.

[0044] In the embodiments of this specification, by designing the differences in thermal expansion coefficients, elastic coefficients, lattice constants, and spontaneous polarization coefficients of the well layer and barrier layer of the quantum well, the thermal mismatch and lattice mismatch of the quantum well can be reduced, the quantum confinement strak effect and the polarization effect of the quantum well can be reduced, the quantum confinement effect can be improved, the electron overflow and valence band order can be reduced, the crystal quality and interface quality of the quantum well can be improved, the overlap probability of the electron-hole wave function of the quantum well can be improved, and the efficiency ratio of the semiconductor light-emitting element in the hot state (e.g., in an environment of 125°C) and the cold state (e.g., in an environment of 25°C) can be improved, such as increasing the hot-cold efficiency ratio from 40% to 80% to 80% to 95%, and suppressing the deterioration of the crystal quality and interface quality during the aging process, reducing the probability of carriers being captured by defects during the aging process, thereby reducing the aging resistance change, and reducing the aging voltage attenuation amplitude from + / -0.05V to 0.1V to + / -0.01~0.05V.

[0045] In some embodiments, the quantum well 102 may further include a first quantum well 102 a , a second quantum well 102 b , and a third quantum well 102 c .

[0046] In some embodiments, the first quantum well 102a, the second quantum well 102b and the third quantum well 102c can be stacked in sequence, as shown in Figure 1, the first quantum well 102a can be attached to the electronic semiconductor 101, the third quantum well 102c can be attached to the electron blocking layer 103 described below, and the second quantum well 102b can be arranged between the first quantum well 102a and the third quantum well 102c.

[0047] In some embodiments, the structures of the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c can be similar, and each quantum well can include at least one periodic structure consisting of the well layer and barrier layer described above. For more information about the well layers and barrier layers of the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c, see Figures 5-8 below and their related descriptions.

[0048] In some embodiments, the optical parameters of the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c differ, such that the optical parameters of the semiconductor light-emitting element are gradient-distributed in at least one direction. The optical parameters may include one or more parameters such as dielectric constant, refractive index, bandgap, and electron effective mass.

[0049] The dielectric constant is the primary parameter reflecting the dielectric or polarization properties of quantum well 102 under the influence of an electrostatic field. The refractive index refers to the change in the speed of light propagating through the quantum well compared to its speed in a vacuum. The band gap is the width of the gap between the energy band where free electrons reside and the energy band where holes reside. The effective mass of an electron is the equivalent mass reflecting the external forces acting on the electron and the pull of internal particles.

[0050] In some embodiments, the at least one direction may include a horizontal direction and / or a thickness direction of the semiconductor light-emitting element. The horizontal direction of the semiconductor light-emitting element may refer to any direction parallel to the horizontal plane projection of the semiconductor light-emitting element. The thickness direction of the semiconductor light-emitting element may refer to a direction perpendicular to the horizontal plane projection of the semiconductor light-emitting element, such as direction x or direction y as shown in FIG1 .

[0051] The gradient distribution may refer to a phased or gradual distribution of the above optical parameters in one or more directions, such as a monotonically decreasing or increasing distribution, a normal distribution, etc. For example, in some embodiments, the gradient distribution of the optical parameters may include a monotonically increasing or decreasing dielectric constant from the first quantum well 102a to the third quantum well 102c.

[0052] In some embodiments, the optical parameters of other components of the semiconductor light-emitting element (e.g., electron-type semiconductor 101, electron-blocking layer 103, and hole-type semiconductor 104) may also be different, so that the overall optical parameters of the semiconductor light-emitting element exhibit a gradient distribution in at least one direction. For more information on the gradient distribution, see Figures 2-3 below and their related descriptions.

[0053] The electron blocking layer 103 is a region that blocks the entry of free electrons. In some embodiments, the material of the electron blocking layer 103 may include one or more dielectric materials such as indium aluminum nitride, aluminum gallium nitride, or gallium nitride. In some embodiments, the electron blocking layer 103 may be disposed between the quantum well 102 and the hole-type semiconductor 104 to prevent electrons traveling within the quantum well 102 from entering the hole-type semiconductor 104. For more information about the electron blocking layer 103, please refer to FIG. 4 and the related description below.

[0054] Hole-type semiconductor 104, also known as a P-type semiconductor, refers to an impurity-containing semiconductor in which the hole concentration is greater than the free electron concentration. Holes are primarily provided by impurity atoms in hole-type semiconductor 104, while free electrons can be formed by thermal excitation. In some embodiments, the impurity concentration of hole-type semiconductor 104 can be positively correlated with the hole concentration. For example, the more impurities doped into hole-type semiconductor 104, the higher the hole concentration.

[0055] In some embodiments, the hole-type semiconductor 104 can be stacked on top of the electron blocking layer described below. In some embodiments, the hole-type semiconductor 104 can provide holes under the action of an external electric field for subsequent recombination with free electrons. For example, as shown in Figure 1, the holes generated by the hole-type semiconductor 104 can move along the second direction (direction y as shown in Figure 1) to the quantum well and recombine with the free electrons. For more information on quantum wells and holes, please refer to the relevant description below.

[0056] In some embodiments, the electron-type semiconductor 101 and the hole-type semiconductor 104 may be made of the same material or different materials. In some embodiments, the materials of the electron-type semiconductor 101 and the hole-type semiconductor 104 may include any one or any combination of AlGaN, GaN, InGaN, InN, AlInN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN, etc.

[0057] In some embodiments, the thickness of the electron-type semiconductor 101 may be within a first preset thickness range. In some embodiments, the thickness of the hole-type semiconductor 104 may be within a second preset thickness range. The first preset thickness range and the second preset thickness range may be determined in various ways, such as manual experience or historical semiconductor data. In some embodiments, the thickness of the electron-type semiconductor 101 may be 5 angstroms to 80,000 angstroms, and the thickness of the hole-type semiconductor 104 may be 5 angstroms to 9,000 angstroms. For example, the thickness of the electron-type semiconductor 101 may be 5 angstroms, 100 angstroms, 5,000 angstroms, or 80,000 angstroms, and the thickness of the hole-type semiconductor 104 may be 5 angstroms, 300 angstroms, 6,500 angstroms, or 9,000 angstroms.

[0058] In the embodiments of this specification, by designing the dielectric constant, refractive index, band gap width and electron effective mass of the quantum well to be gradiently distributed in at least one direction, the reflection and refraction of light can be improved, the luminous angle of the outgoing light can be increased, and the light emission path can be changed to improve the light extraction efficiency.

[0059] In addition, by designing the differences in the thermal expansion coefficient, elastic coefficient, lattice constant, and spontaneous polarization coefficient of the well layer and barrier layer of the quantum well, the thermal mismatch and lattice mismatch of the quantum well can be reduced, the quantum confinement strak effect and the polarization effect of the quantum well can be reduced, the quantum confinement effect can be improved, the electron overflow and valence band order can be reduced, the crystal quality and interface quality of the quantum well can be improved, the overlap probability of the electron-hole wave function of the quantum well can be increased, the hot-cold efficiency ratio of the semiconductor light-emitting element can be increased, and the deterioration of the crystal quality and interface quality during the aging process can be suppressed, the probability of carriers being captured by defects during the aging process can be reduced, and the aging resistance change can be reduced.

[0060] Figure 2 is a SIMS secondary ion mass spectrum of the structure of a semiconductor light-emitting element provided in an embodiment of this specification, and Figure 3 is a SIMS secondary ion mass spectrum of the local structure of a quantum well of a semiconductor light-emitting element provided in an embodiment of this specification. As shown in Figures 2 and 3, the horizontal axis can represent the thickness of the semiconductor light-emitting element, and the vertical axis can represent the concentration distribution of elements in the semiconductor light-emitting element.

[0061] In some embodiments, the dielectric constant of the semiconductor light-emitting element can be gradient distributed within a preset dielectric range. The preset dielectric range can be set based on manual experience or historical data. For example, the preset dielectric range can include [8, 12]. In some embodiments, the dielectric constant of the electron-type semiconductor 101 is a, the dielectric constant of the well layer of the first quantum well 102a is b, the dielectric constant of the well layer of the second quantum well 102b is c, the dielectric constant of the well layer of the third quantum well 102c is d, the dielectric constant of the electron blocking layer 103 is e, and the dielectric constant of the hole-type semiconductor 104 is f. The dielectric constant of the semiconductor light-emitting element includes the following gradient relationship: 12≥d≥c≥b≥f≥a≥e≥8.

[0062] For example, the dielectric constant of the electron-type semiconductor 101 is 9, the dielectric constant of the well layer of the first quantum well 102a is 10.9, the dielectric constant of the well layer of the second quantum well 102b is 11.5, the dielectric constant of the well layer of the third quantum well 102c is 12, the dielectric constant of the electron blocking layer 103 is 8, the dielectric constant of the hole-type semiconductor 104 is 10.2, and the dielectric constant of the semiconductor light-emitting element includes the following gradient relationship: 12≥d≥c≥b≥f≥a≥e≥8.

[0063] In the embodiments of this specification, by designing the dielectric constant to be distributed in a gradient in at least one direction and by adjusting the gradient distribution of the dielectric constant, the reflection and refraction of the light output by the semiconductor light-emitting element can be controlled, thereby controlling the luminous angle of the emitted light and improving the light extraction efficiency of the semiconductor light-emitting element.

[0064] In some embodiments, the refractive index coefficient of the semiconductor light-emitting element can be gradiently distributed within a preset refractive range. The preset refractive range can be set based on manual experience or historical data. For example, the preset refractive range may include [1.5, 3.5]. In some embodiments, the refractive index coefficient of the electron-type semiconductor 101 is g, the refractive index coefficient of the well layer of the first quantum well 102a is h, the refractive index coefficient of the well layer of the second quantum well 102b is i, the refractive index coefficient of the well layer of the third quantum well 102c is j, the refractive index coefficient of the electron blocking layer 103 is k, and the refractive index coefficient of the hole-type semiconductor 104 is l. The refractive index coefficient of the semiconductor light-emitting element includes the following gradient relationship: 3.5≥j≥i≥h≥l≥g≥k≥1.5.

[0065] For example, the refractive index coefficient of the electron-type semiconductor 101 is 2, the refractive index coefficient of the well layer of the first quantum well 102a is 3.2, the refractive index coefficient of the well layer of the second quantum well 102b is 3.2, the refractive index coefficient of the well layer of the third quantum well 102c is 3.5, the refractive index coefficient of the electron blocking layer 103 is 1.5, and the refractive index coefficient of the hole-type semiconductor 104 is 2.5.

[0066] In the embodiments of this specification, by designing the refractive index coefficient to be distributed in a gradient in at least one direction, the reflection and refraction of light can be improved, the luminous angle of the emitted light can be increased, and the light extraction efficiency of the semiconductor light-emitting element can be improved.

[0067] In some embodiments, the bandgap width of the semiconductor light-emitting element can be gradiently distributed within a preset bandgap range. The preset bandgap range can be set based on manual experience or historical data. For example, the preset refractive index range can include [0.5eV, 6.5eV]. In some embodiments, the bandgap width of the electron-type semiconductor 101 is u, the bandgap width of the well layer of the first quantum well 102a is v, the bandgap width of the well layer of the second quantum well 102b is w, the bandgap width of the well layer of the third quantum well 102c is x, the bandgap width of the electron blocking layer 103 is y, and the bandgap width of the hole-type semiconductor 104 is z. The bandgap width of the semiconductor light-emitting element includes the following gradient relationship: 6.5eV≥y≥u≥z≥v≥w≥x≥0.5eV.

[0068] Exemplarily, the band gap width of the electron-type semiconductor 101 is 5.5 eV, the band gap width of the well layer of the first quantum well 102a is 3 eV, the band gap width of the well layer of the second quantum well 102b is 2.1 eV, the band gap width of the well layer of the third quantum well 102c is 0.5 eV, the band gap width of the electron blocking layer 103 is 6.5 eV, and the band gap width of the hole-type semiconductor 104 is 4.5 eV.

[0069] In the embodiments of this specification, by designing the bandgap width to be gradiently distributed in at least one direction, the overlap probability and overlap position of electron and hole wave functions can be improved, and the light emission path can be changed to improve light extraction efficiency.

[0070] In some embodiments, the electron effective mass of the semiconductor light-emitting element can be distributed in a gradient within a preset mass range. The preset mass range can be set based on manual experience or historical data. For example, the preset mass range can include [1.5, 3.5]. In some embodiments, the electron effective mass of the electron-type semiconductor 101 is o, the electron effective mass of the well layer of the first quantum well 102a is p, the electron effective mass of the well layer of the second quantum well 102b is q, the electron effective mass of the well layer of the third quantum well 102c is r, the electron effective mass of the electron blocking layer 103 is s, and the electron effective mass of the hole-type semiconductor 104 is t. The electron effective mass of the semiconductor light-emitting element includes the following gradient relationship: 10m e ≥s≥o≥t≥p≥q≥r≥0.01m e .

[0071] For example, the electron effective mass of the electronic semiconductor 101 is 7m eThe effective mass of electrons in the well layer of the first quantum well 102a is 5.5m e The effective mass of electrons in the well layer of the second quantum well 102b is 3m e The effective mass of electrons in the well layer of the third quantum well 102c is 0.01m e , the effective mass of electrons in the electron blocking layer 103 is 10m e , the effective mass of the electron in the hole-type semiconductor 104 is 7m e .

[0072] In the embodiments of this specification, by designing the dielectric constant and the refractive index to be gradiently distributed in at least one direction, the reflection and refraction of light can be improved, and the luminous angle of the emitted light can be increased. For example, the luminous angle can be increased from at least 80° to 120° to 120° to 200°, and the band gap width and the electron effective mass are set to be gradiently distributed in at least one direction. This can improve the overlap probability and overlap position of the electron and hole wave functions, and can change the light emission path and improve the light extraction efficiency, such as at least increasing the light extraction efficiency from 40% to 60% to 60% to 95%.

[0073] FIG2 is a structural SIMS secondary ion mass spectrum of a semiconductor light-emitting element provided in an embodiment of the present specification, and FIG3 is a structural SIMS secondary ion mass spectrum of a local structure of a quantum well of a semiconductor light-emitting element provided in an embodiment of the present specification. As shown in FIG2-FIG3, the horizontal axis can represent the thickness of the semiconductor light-emitting element, and the vertical axis can represent the concentration of the element in the semiconductor light-emitting element. Correspondingly, the broken line shown in FIG2-FIG3 can represent the element concentration of the element corresponding to the broken line at a certain thickness in the semiconductor light-emitting element, and the broken line can represent the concentration distribution of the element corresponding to the broken line in the semiconductor light-emitting element. For example, the broken lines corresponding to the In element in the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c are distributed in a wavy manner, that is, the concentration of the In element in the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c is distributed in a wavy manner.

[0074] In some embodiments, the electron blocking layer may be doped with multiple elements, and the multiple elements may exhibit different concentration distributions in at least one direction. The multiple elements may include one or more elements such as Mg, Al, In, Si, C, H, and O. In some embodiments, the at least one direction may include a direction toward the quantum well, a direction toward the interface of the quantum well, and the like. In some embodiments, the concentration distribution may include one or more distributions such as a parabolic distribution, an M-shaped distribution, and a gradient-descent distribution.

[0075] Figure 4 is a SIMS secondary ion mass spectrum of the local structure of an electron blocking layer of a semiconductor light-emitting element provided in an embodiment of this specification. Figure 8 is a transmission electron microscopy (TEM) image of an electron blocking layer of a semiconductor light-emitting element provided in an embodiment of this specification. In some embodiments, as shown in Figures 4 and 8, electron blocking layer 103 may include a Mg doping concentration distribution, an Al element concentration distribution, an In element concentration distribution, a Si doping concentration distribution, a C element concentration distribution, a H element concentration distribution, and an O element concentration distribution in at least one direction.

[0076] In some embodiments, as shown in FIG4 , the Mg doping concentration distribution of the electron blocking layer 103 is parabolic, with the peak position of the Mg doping concentration distribution decreasing toward the interface of the quantum well 102, and the decreasing angle of the Mg doping concentration distribution is φ. The "interface toward the quantum well 102" refers to the direction from the electron blocking layer 103 to the interface between the electron blocking layer 103 and the quantum well 102.

[0077] The decline angle refers to the degree of change in the decline distribution of elements in the electron blocking layer 103. In some embodiments, the decline angle φ of the Mg doping concentration distribution can reflect the change in the decline distribution of the Mg doping concentration distribution from the electron blocking layer 103 to the quantum well 102. In some embodiments, the decline angle φ of the Mg doping concentration distribution can be within a preset Mg angle range, which can be determined based on manual experience or historical data. In some embodiments, the decline angle φ of the Mg doping concentration distribution can be 30°≤φ≤90°. For example, the decline angle φ of the Mg doping concentration distribution can be 30°, 45°, 60°, or 90°.

[0078] In some embodiments, as shown in FIG4 , the Si doping concentration distribution of the electron blocking layer 103 may be W-shaped, with the Si doping concentration distribution showing a downward trend toward the quantum well, and the decreasing angle of the Si doping concentration distribution is θ, which is similar to the decreasing angle φ of the above-mentioned Mg doping concentration distribution. In some embodiments, the decreasing angle θ of the Si doping concentration distribution may be within a preset Si angle range, and the preset Si angle range may be determined based on manual experience or historical data. In some embodiments, the decreasing angle θ of the Si doping concentration distribution may be 20°≤θ≤85°. Exemplarily, the decreasing angle θ of the Si doping concentration distribution may be 20°, 45°, 60°, or 85°.

[0079] In some embodiments, as shown in FIG4 , the Al element concentration distribution of the electron blocking layer 103 is M-shaped, and the peak position of the Al element concentration distribution is downward in the direction of the quantum well 102. The decreasing angle of the Al element concentration distribution is α, which is similar to the decreasing angle φ of the above-mentioned Mg doping concentration distribution. In some embodiments, the decreasing angle α of the Al element concentration distribution can be within a preset Al angle range, and the preset Al angle range can be determined based on manual experience or historical data. In some embodiments, the decreasing angle α of the Al element concentration distribution can be 10°≤α≤80°. Exemplarily, the decreasing angle α of the Al element concentration distribution can be 10°, 45°, 70°, or 80°.

[0080] In some embodiments, as shown in FIG4 , the In element concentration distribution of the electron blocking layer 103 may be parabolic, and the peak position of the In element concentration distribution shows a downward trend toward the quantum well, and the decreasing angle of the In element concentration distribution is ρ, which is similar to the decreasing angle φ of the above-mentioned Mg doping concentration distribution.

[0081] In some embodiments, the decreasing angle p of the In element concentration distribution may be within a preset In angle range, which may be determined based on manual experience or historical data. In some embodiments, the decreasing angle p of the In element concentration distribution may be 15°≤p≤85°. For example, the decreasing angle p of the In element concentration distribution may be 15°, 55°, 60°, or 85°.

[0082] In some embodiments, as shown in FIG4 , the peak position of the H element concentration distribution of the electron blocking layer 103 shows a downward trend toward the quantum well, and the decreasing angle of the H element concentration distribution is ε, which is similar to the decreasing angle φ of the Mg doping concentration distribution described above. In some embodiments, the decreasing angle ε of the H element concentration distribution can be within a preset H angle range, which can be determined based on manual experience or historical data. In some embodiments, the decreasing angle ε of the H element concentration distribution can be 15°≤ε≤85°. For example, the decreasing angle ε of the H element concentration distribution can be 15°, 55°, 65°, or 85°.

[0083] In some embodiments, as shown in Figure 4, the peak position of the C element concentration distribution of the electron blocking layer 103 shows a downward trend toward the quantum well 102, and the descending angle of the C element concentration distribution is δ. The descending angle δ of the C element concentration distribution is similar to the descending angle φ of the above-mentioned Mg doping concentration distribution. In some embodiments, the descending angle δ of the C element concentration distribution can be within a preset C angle range, and the preset C angle range can be determined based on manual experience or historical data. In some embodiments, the descending angle δ of the C element concentration distribution can be 10°≤δ≤80°. Exemplarily, the descending angle δ of the C element concentration distribution can be 10°, 55°, 65°, or 80°.

[0084] In some embodiments, as shown in FIG4 , the peak position of the O element concentration distribution shows a downward trend toward the quantum well (102), and the O element concentration distribution decreases at an angle of ψ. The O element concentration distribution decreases at an angle ψ, similar to the decrease angle φ of the above-mentioned Mg doping concentration distribution. In some embodiments, the O element concentration distribution decreases at an angle ψ within a preset O angle range, which can be determined based on manual experience or historical data. In some embodiments, the O element concentration distribution decreases at an angle ψ of 25°≤ψ≤85. Exemplarily, the O element concentration distribution decreases at an angle ψ of 25°, 45°, 55°, or 85°.

[0085] In the embodiments of this specification, by designing the Mg doping concentration distribution, Al element concentration distribution, In element concentration distribution, Si doping concentration distribution, C element concentration distribution, H element concentration distribution and O element concentration distribution of the electron blocking layer 103, a two-dimensional electron gas, a three-dimensional electron gas, a two-dimensional composite hole gas or a three-dimensional composite hole gas can be formed, which can improve the efficiency of hole injection into the quantum well and the hole transport efficiency, reduce the efficiency attenuation of the semiconductor light-emitting element under large current injection, improve the lateral and longitudinal expansion of electrons and holes, reduce the conductive resistance and series resistance, reduce the voltage of the semiconductor light-emitting element, and at the same time improve the anti-static discharge (ESD) capability.

[0086] In some embodiments, the descending angle of the electron blocking layer 103 may have different distribution relationships within a preset descending angle range. The descending angle range may be determined based on various methods, such as manual experience or historical data. In some embodiments, the descending angle of the electron blocking layer 103 may have the following relationship: 10° ≤ α ≤ δ ≤ ρ ≤ ε ≤ θ ≤ ψ ≤ φ ≤ 85°.

[0087] For example, the decreasing angle φ of the Mg doping concentration distribution can be 85°, the decreasing angle θ of the Si doping concentration distribution can be 50°, the decreasing angle α of the Al element concentration distribution can be 10°, the decreasing angle ρ of the In element concentration distribution can be 35°, the decreasing angle ε of the H element concentration distribution can be 45°, the decreasing angle δ of the C element concentration distribution can be 20°, and the decreasing angle ψ of the O element concentration distribution can be 60°.

[0088] In the embodiments of this specification, by designing the descending angle of the Mg doping concentration distribution, the descending angle of the Al element concentration distribution, the descending angle of the In element concentration distribution, the descending angle of the Si doping concentration distribution, the descending angle of the C element concentration distribution, the descending angle of the H element concentration distribution and the descending angle of the O element concentration distribution of the electron blocking layer 103, the efficiency of hole injection into the quantum well and the hole transport efficiency can be improved, and the efficiency attenuation of the semiconductor light-emitting element under large current injection can be reduced, thereby reducing the conductive resistance and series resistance, reducing the voltage of the semiconductor light-emitting element, and improving the ability to resist electrostatic release.

[0089] In some embodiments, the electron effective mass distribution, piezoelectric polarization coefficient distribution, and dielectric constant distribution of the electron blocking layer 103 may have different distribution relationships, wherein the distribution relationships may be determined based on various methods such as manual experience or historical data.

[0090] In some embodiments, as shown in Figure 4, the electron blocking layer 103 also includes an electron effective mass distribution with a V-shaped distribution; the electron blocking layer 103 includes a piezoelectric polarization coefficient distribution with an M-shaped distribution; the electron blocking layer 103 includes an inverted V-shaped dielectric constant distribution; or the electron blocking layer 103 includes an M-shaped electron effective mass distribution; the electron blocking layer 103 includes an Al / O element concentration ratio distribution with an M-type distribution and an In / O element concentration ratio distribution with an N-type distribution; the electron blocking layer 103 includes a Mg / O element concentration ratio distribution with a parabolic distribution.

[0091] In the embodiments of the present specification, by designing the descending angle of the Mg doping concentration distribution, the descending angle of the Si doping concentration distribution, the descending angle of the Al element concentration distribution, the descending angle of the In element concentration distribution, the descending angle of the H element concentration distribution, the descending angle of the C element concentration distribution, the descending angle of the O element concentration distribution, and the M-type piezoelectric polarization coefficient distribution, the inverted V-type dielectric constant distribution, and the M-type electron effective mass distribution of the electron blocking layer 103, a two-dimensional electron gas, a three-dimensional electron gas, a two-dimensional composite hole gas, or a three-dimensional composite hole gas can be formed, thereby improving the efficiency of hole injection quantum wells and the hole transport efficiency, reducing the efficiency attenuation of semiconductor light-emitting elements under large current injection, such as reducing the efficiency attenuation from 40% to 70% to 5% to 35%, and increasing the lateral and longitudinal expansion of electrons and holes, reducing the conductive resistance and series resistance, and reducing the voltage of the semiconductor light-emitting element, such as reducing the voltage from 3.05V to below 2.9V. At the same time, the anti-static release (Electro-Static discharge (ESD) capability, such as the 8KV ESD pass rate is increased from below 60% to over 90%.

[0092] In some embodiments, the first quantum well 102 a , the second quantum well 102 b , and the third quantum well 102 c may also have different materials, thicknesses, element concentration distributions, and the like.

[0093] Figure 5 is a transmission electron microscope TEM image of the first quantum well of a semiconductor light-emitting element provided in an embodiment of this specification; Figure 6 is a transmission electron microscope TEM image of the second quantum well of a semiconductor light-emitting element provided in an embodiment of this specification; Figure 7 is a transmission electron microscope TEM image of the third quantum well of a semiconductor light-emitting element provided in an embodiment of this specification.

[0094] In some embodiments, as shown in FIG5 , the well layer of the first quantum well 102 a includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the thickness of the well layer of the first quantum well 102 a is 5 angstroms to 80 angstroms. For example, the thickness of the well layer of the first quantum well 102 a can be 5 angstroms, 25 angstroms, 50 angstroms, or 80 angstroms.

[0095] In some embodiments, the barrier layer of the first quantum well 102a includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the first quantum well 102a is 10 angstroms to 500 angstroms. For example, the thickness of the barrier layer of the first quantum well 102a can be 10 angstroms, 25 angstroms, 200 angstroms, or 500 angstroms.

[0096] In some embodiments, the Al element concentration distribution of the first quantum well (102a) shows a decreasing trend toward the electronic semiconductor, and the decreasing angle of the Al element concentration distribution is ν, and the angle range of ν is 15°≤ν≤75°. For example, the decreasing angle ν of the Al element concentration distribution can be 15°, 20°, 45°, or 75°.

[0097] In some embodiments, the C / O element concentration ratio distribution of the first quantum well (102a) is V-shaped, with the C / O element concentration ratio distribution decreasing toward the hole-type semiconductor 101. The decreasing angle of the C / O element concentration ratio distribution is ω, and the angle range of ω is 20°≤ω≤80°. For example, the decreasing angle ω of the C / O element concentration ratio distribution can be 20°, 30°, 45°, or 80°.

[0098] In some embodiments, the C / O element concentration ratio distribution may include one or more ratios such as the concentration ratio and mass ratio of the C element and the O element.

[0099] In some embodiments, as shown in FIG6 , the well layer of the second quantum well 102 b includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the well layer thickness of the second quantum well 102 b is 5 angstroms to 100 angstroms. For example, the well layer thickness of the second quantum well 102 b can be 10 angstroms, 25 angstroms, 200 angstroms, or 100 angstroms.

[0100] In some embodiments, the barrier layer of the second quantum well 102 b includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the second quantum well 102 b is 10 angstroms to 300 angstroms. For example, the thickness of the barrier layer of the second quantum well 102 b can be 10 angstroms, 50 angstroms, 200 angstroms, or 300 angstroms.

[0101] In some embodiments, the Al concentration distribution of the second quantum well 102b decreases toward the electronic semiconductor. The decreasing angle of the Al concentration distribution is μ, and the angle range of μ is 20°≤μ≤80°. For example, the decreasing angle μ of the Al concentration distribution can be 20°, 30°, 65°, or 80°.

[0102] In some embodiments, the C / O element concentration ratio distribution of the second quantum well 102b exhibits an L-shaped distribution, wherein the C / O element concentration ratio distribution decreases toward the hole-type semiconductor. The decreasing angle of the C / O element concentration ratio distribution is γ, and the angle range of γ is 25°≤γ≤85°. For example, the decreasing angle γ of the C / O element concentration ratio distribution can be 25°, 50°, 65°, or 85°.

[0103] In some embodiments, as shown in FIG7 , the well layer of the third quantum well 102 c includes any one or any combination of InGaN, GaN, AlGaN, AlInGaN, and AlInN, and the well layer thickness of the third quantum well 102 c is 5 angstroms to 150 angstroms. For example, the well layer thickness of the third quantum well 102 c can be 5 angstroms, 50 angstroms, 80 angstroms, or 150 angstroms.

[0104] In some embodiments, the barrier layer of the third quantum well 102c is any one or any combination of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, and the thickness of the barrier layer of the third quantum well 102c is 10 angstroms to 200 angstroms. For example, the thickness of the barrier layer of the third quantum well 102c can be 10 angstroms, 50 angstroms, 90 angstroms, or 200 angstroms.

[0105] In some embodiments, the Al concentration distribution of the third quantum well 102c decreases toward the electronic semiconductor. The decreasing angle of the Al concentration distribution is λ, and the angle range of λ is 30°≤λ≤90°. For example, the decreasing angle λ of the Al concentration distribution can be 30°, 50°, 65°, or 90°.

[0106] In some embodiments, the C / O element concentration ratio distribution of the third quantum well 102c shows a decreasing trend toward the electronic semiconductor. The decreasing angle of the C / O element concentration ratio distribution is β, and the angle range of β is 10°≤β≤70°. For example, the decreasing angle β of the C / O element concentration ratio distribution can be 10°, 50°, 65°, or 70°.

[0107] In some embodiments, the H / O element concentration ratio distribution of the third quantum well 102c shows a decreasing trend toward the electronic semiconductor. The decreasing angle of the H / O element concentration ratio distribution is κ, and the angle range of κ is 20°≤κ≤80°. For example, the decreasing angle κ of the H / O element concentration ratio distribution can be 20°, 50°, 60°, or 80°.

[0108] In some embodiments, the Al / O element drop angle, the C / O element concentration ratio distribution drop angle, and the H / O element concentration ratio distribution drop angle of the first quantum well 102a, the second quantum well 102b, and the third quantum well 102c have the following relationship: 10°≤β≤ν≤μ≤ω≤κ≤γ≤λ≤90°.

[0109] For example, the decreasing angle ν of the Al element concentration distribution in the first quantum well 102a can be 15°, and the decreasing angle ω of the C / O element concentration ratio distribution can be 45°; the decreasing angle μ of the Al element concentration distribution in the second quantum well 102b can be 30°, and the decreasing angle γ of the C / O element concentration ratio distribution can be 60°; the decreasing angle λ of the Al element concentration distribution in the third quantum well 102c can be 90°, the decreasing angle β of the C / O element concentration ratio distribution can be 10°, and the decreasing angle κ of the H / O element concentration ratio distribution can be 50°.

[0110] In the embodiments of this specification, by designing the element ratio and angle change of the quantum well, the stress release at the interface between the well layer and the barrier layer of the quantum well can be enhanced, the stress at the interface between the well layer and the barrier layer of the quantum well can be reduced, and the stress mismatch and non-radiative recombination centers such as SRH and Auger recombination of the quantum well can be further reduced. The electron overflow barrier is increased and the hole injection barrier is reduced, the radiative recombination efficiency of the quantum well is improved, the electron overflow and hole overflow under large current injection conditions are reduced, and the quantum localization effect of the quantum well is enhanced, thereby reducing the efficiency droop of the semiconductor light-emitting element under large current injection, such as the efficiency droop is reduced from 40% to 70% to 5% to 35%.

[0111] While the basic concepts have been described above, it will be apparent to those skilled in the art that the detailed disclosure is merely illustrative and does not limit this specification. Although not explicitly stated herein, various modifications, improvements, and revisions to this specification may be made by those skilled in the art. Such modifications, improvements, and revisions are suggested in this specification and remain within the spirit and scope of the exemplary embodiments of this specification.

[0112] This specification also uses specific terms to describe the embodiments of this specification. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "one embodiment," "an embodiment," or "an alternative embodiment" two or more times in different locations in this specification do not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of this specification may be appropriately combined.

[0113] In addition, unless expressly stated in the claims, the order of the processing elements and sequences, the use of alphanumeric characters, or the use of other names described in this specification are not intended to limit the order of the processes and methods of this specification. Although the above disclosure discusses some of the invention embodiments currently considered useful through various examples, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the spirit and scope of the embodiments of this specification. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.

[0114] Similarly, it should be noted that, in order to simplify the presentation of this specification and thus facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this specification sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not imply that the subject matter of this specification requires more features than those recited in the claims. In fact, an embodiment may have fewer features than all of the features of a single disclosed embodiment.

[0115] In some embodiments, numbers are used to describe the quantity of components and attributes. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise stated, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the description and claims are approximate values, which may change according to the required characteristics of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of this specification are approximate values, in specific embodiments, the settings of such numerical values ​​are as accurate as possible within the feasible range.

[0116] Each patent, patent application, patent application publication, and other materials, such as articles, books, specifications, publications, and documents, cited in this specification is hereby incorporated by reference in its entirety. This includes application history documents that are inconsistent with or conflict with the content of this specification, as well as documents (currently or subsequently attached to this specification) that limit the broadest scope of the claims of this specification. It should be noted that if the descriptions, definitions, and / or terminology used in the accompanying materials are inconsistent or conflicting with the content of this specification, the descriptions, definitions, and / or terminology used in this specification will control.

[0117] Finally, it should be understood that the embodiments described in this specification are intended only to illustrate the principles of the embodiments of this specification. Other variations may also fall within the scope of this specification. Therefore, by way of example and not limitation, alternative configurations of the embodiments of this specification may be considered consistent with the teachings of this specification. Accordingly, the embodiments of this specification are not limited to the embodiments explicitly described and illustrated in this specification.

Claims

1. A semiconductor light emitting element, characterized in that: include: A substrate (100), an electron-type semiconductor (101), a quantum well (102), an electron blocking layer (103), and a hole-type semiconductor (104) are sequentially stacked; The quantum well (102) comprises a first quantum well (102a), a second quantum well (102b) and a third quantum well (102c); the dielectric constant, refractive index, bandgap width and electron effective mass of the first quantum well (102a), the second quantum well (102b) and the third quantum well (102c) are different, so that the dielectric constant, refractive index, bandgap width and electron effective mass of the semiconductor light emitting element are distributed in a gradient in at least one direction; The quantum well (102) comprises a periodic structure consisting of a well layer and a barrier layer, the period number of the periodic structure is 1 to 50; the thermal expansion coefficient of the well layer is less than or equal to the thermal expansion coefficient of the barrier layer; the elastic coefficient of the well layer is less than or equal to the elastic coefficient of the barrier layer; the lattice constant of the well layer is greater than or equal to the lattice constant of the barrier layer; and the spontaneous polarization coefficient of the well layer is less than or equal to the spontaneous polarization coefficient of the barrier layer.

2. The semiconductor light emitting element according to claim 1, characterized in that The dielectric constant of the electron-type semiconductor (101) is a, the dielectric constant of the well layer of the first quantum well (102a) is b, the dielectric constant of the well layer of the second quantum well (102b) is c, the dielectric constant of the well layer of the third quantum well (102c) is d, the dielectric constant of the electron blocking layer (103) is e, the dielectric constant of the hole-type semiconductor (104) is f, and the dielectric constant of the semiconductor light-emitting element includes the following gradient relationship: 12≥d≥c≥b≥f≥a≥e≥8.

3. The semiconductor light emitting element according to claim 1, characterized in that The refractive index coefficient of the electron-type semiconductor (101) is g, the refractive index coefficient of the well layer of the first quantum well (102a) is h, the refractive index coefficient of the well layer of the second quantum well (102b) is i, the refractive index coefficient of the well layer of the third quantum well (102c) is j, the refractive index coefficient of the electron blocking layer (103) is k, the refractive index coefficient of the hole-type semiconductor (104) is l, and the refractive index coefficient of the semiconductor light-emitting element includes the following gradient relationship: 3.5≥j≥i≥h≥l≥g≥k≥1.

5.

4. The semiconductor light emitting element according to claim 1, characterized in that The bandgap width of the electron-type semiconductor (101) is u, the bandgap width of the well layer of the first quantum well (102a) is v, the bandgap width of the well layer of the second quantum well (102b) is w, the bandgap width of the well layer of the third quantum well (102c) is x, the bandgap width of the electron blocking layer (103) is y, the bandgap width of the hole-type semiconductor (104) is z, and the bandgap width of the semiconductor light-emitting element includes the following gradient relationship: 6.5eV≥y≥u≥z≥v≥w≥x≥0.5eV.

5. The semiconductor light emitting element according to claim 1, characterized in that: The electron effective mass of the electron-type semiconductor (101) is o, the electron effective mass of the well layer of the first quantum well (102a) is p, the electron effective mass of the well layer of the second quantum well (102b) is q, the electron effective mass of the well layer of the third quantum well (102c) is r, the electron effective mass of the electron blocking layer (103) is s, the electron effective mass of the hole-type semiconductor (104) is t, and the electron effective mass of the semiconductor light-emitting element includes the following gradient relationship: 10m e ≥s≥o≥t≥p≥q≥r≥0.01m e .

6. The semiconductor light emitting element according to claim 1, characterized in that The electron blocking layer (103) includes, in at least one direction, a Mg doping concentration distribution, an Al element concentration distribution, an In element concentration distribution, a Si doping concentration distribution, a C element concentration distribution, an H element concentration distribution, and an O element concentration distribution; The Mg doping concentration distribution of the electron blocking layer (103) is parabolic, the peak position of the Mg doping concentration distribution is decreasing in the direction of the interface of the quantum well, the decreasing angle of the Mg doping concentration distribution is φ, and the angle range of φ is 30°≤φ≤90°; The Si doping concentration distribution of the electron blocking layer (103) is W-shaped, the Si doping concentration distribution is decreasing in the direction of the quantum well, the decreasing angle of the Si doping concentration distribution is θ, and the angle range of θ is 20°≤θ≤85°; The Al element concentration distribution of the electron blocking layer (103) is M-shaped, the peak position of the Al element concentration distribution is decreasing in the direction of the quantum well, the decreasing angle of the Al element concentration distribution is α, and the angle range of α is 10°≤α≤80°; The In element concentration distribution of the electron blocking layer (103) is parabolic, the peak position of the In element concentration distribution is decreasing in the direction of the quantum well, the decreasing angle of the In element concentration distribution is ρ, and the angle range of ρ is 15°≤ρ≤85°; The peak position of the H element concentration distribution of the electron blocking layer (103) shows a downward trend toward the direction of the quantum well, the downward angle of the H element concentration distribution is ε, and the angle range of ε is 15°≤ε≤85°; The peak position of the C element concentration distribution of the electron blocking layer (103) shows a downward trend toward the quantum well (102), the decreasing angle of the C element concentration distribution is δ, and the angle range of δ is 10°≤δ≤80°; The peak position of the O element concentration distribution of the electron blocking layer (103) shows a downward trend toward the quantum well (102), the O element concentration distribution decreases at an angle of ψ, and the angle range of ψ is 25°≤ψ≤85°.

7. The semiconductor light emitting element according to claim 6, characterized in that: The descending angle of the electron blocking layer (103) includes the following relationship: 10°≤α≤δ≤ρ≤ε≤θ≤ψ≤φ≤85°.

8. The semiconductor light emitting element according to claim 6, characterized in that The electron blocking layer (103) further comprises an electron effective mass distribution in a V-shaped distribution or an M-shaped distribution; the electron blocking layer (103) comprises a piezoelectric polarization coefficient distribution in an M-shaped distribution; the electron blocking layer (103) comprises a dielectric constant distribution in an inverted V-shaped distribution; the electron blocking layer (103) comprises an Al / O element concentration ratio distribution in an M-shaped distribution and an In / O element concentration ratio distribution in an N-shaped distribution; the electron blocking layer (103) comprises a Mg / O element concentration ratio distribution in a parabolic distribution.

9. The semiconductor light emitting element according to claim 1, characterized in that: in, The well layer of the first quantum well (102a) comprises any one of InGaN, GaN, AlGaN, AlInGaN, and AlInN, or any combination thereof, and the thickness of the well layer of the first quantum well (102a) is 5 angstroms to 80 angstroms; the barrier layer of the first quantum well (102a) comprises any one of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, or any combination thereof, and the thickness of the barrier layer of the first quantum well (102a) is 10 to 50 angstroms. 0 angstroms; the Al element concentration distribution of the first quantum well (102a) shows a downward trend toward the electron-type semiconductor, the downward angle of the Al element concentration distribution is ν, and the angle range of ν is 15°≤ν≤75°; the C / O element concentration ratio distribution of the first quantum well (102a) shows a V-shaped distribution, the C / O element concentration ratio distribution shows a downward trend toward the hole-type semiconductor, the downward angle of the C / O element concentration ratio distribution is ω, and the angle range of ω is 20°≤ω≤80°; The well layer of the second quantum well (102b) comprises any one of InGaN, GaN, AlGaN, AlInGaN, and AlInN, or any combination thereof, and the thickness of the well layer of the second quantum well (102b) is 5 angstroms to 100 angstroms; the barrier layer of the second quantum well (102b) comprises any one of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, or any combination thereof, and the thickness of the barrier layer of the second quantum well (102b) is 10 angstroms to 30 angstroms. 0 angstroms; the Al element concentration distribution of the second quantum well (102b) shows a downward trend toward the electron-type semiconductor, the downward angle of the Al element concentration distribution is μ, and the angle range of μ is 20°≤μ≤80°; the C / O element concentration ratio distribution of the second quantum well (102b) shows an L-shaped distribution, the C / O element concentration ratio distribution shows a downward trend toward the hole-type semiconductor, the downward angle of the C / O element concentration ratio distribution is γ, and the angle range of γ is 25°≤γ≤85°; The well layer of the third quantum well (102c) comprises any one of InGaN, GaN, AlGaN, AlInGaN, and AlInN, or any combination thereof, and the well layer thickness of the third quantum well (102c) is 5 angstroms to 150 angstroms; the barrier layer of the third quantum well (102c) comprises any one of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, or any combination thereof, and the third quantum well (102c) comprises any one of InGaN, GaN, AlGaN, AlInGaN, AlInN, and AlN, or any combination thereof. The thickness of the barrier layer is 10 angstroms to 200 angstroms; the Al element concentration distribution of the third quantum well (102c) shows a downward trend toward the electronic semiconductor direction, the downward angle of the Al element concentration distribution is λ, and the angle range of λ is 30°≤λ≤90°; the C / O element concentration ratio distribution of the third quantum well (102c) shows a downward trend toward the electronic semiconductor direction, the downward angle of the C / O element concentration ratio distribution is β, and the angle range of β is 10°≤β≤70°; the H / O element concentration ratio distribution of the third quantum well (102c) shows a downward trend toward the electronic semiconductor direction, the downward angle of the H / O element concentration ratio distribution is κ, and the angle range of κ is 20°≤κ≤80°; The Al / O element descent angle, the C / O element concentration ratio distribution descent angle, and the H / O element concentration ratio distribution descent angle of the first quantum well (102a), the second quantum well (102b), and the third quantum well (102c) include the following relationship: 10°≤β≤ν≤μ≤ω≤κ≤γ≤λ≤90°.

10. The semiconductor light emitting element according to claim 1, characterized in that: The electron-type semiconductor (101) and the hole-type semiconductor (104) include AlGaN, GaN, InGaN, InN, AlInN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN; the thickness of the electronic semiconductor (101) is 5 angstroms to 80,000 angstroms, and the thickness of the hole-type semiconductor (104) is 5 angstroms to 9,000 angstroms; the substrate (100) includes any one or more combinations of sapphire, silicon, Ge, SiC, AlN, InAs, GaSb, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiNx, magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrates.

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