A nitride semiconductor light-emitting diode

Abstract

This invention proposes a nitride semiconductor light-emitting diode (LED), comprising, from bottom to top, a substrate, an n-type semiconductor, a quantum well, and a p-type semiconductor. The quantum well is a periodic structure composed of a well layer and a barrier layer. A p-type contact layer is disposed above the p-type semiconductor. The p-type contact layer exhibits saturated electron drift velocity distribution characteristics, effective light hole mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics. This invention can enhance hole transport and conduction in the p-type contact layer, improve the lateral and longitudinal expansion capabilities of holes in the p-type contact layer, and improve the surge capability and human body mode electrostatic discharge (HBD) immunity of the LED. The HBD immunity is improved from a pass rate of over 90% for 100–200V to over 90% for 200–500V.

Description

Technical Field

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

[0005] This invention provides a nitride semiconductor light-emitting diode, comprising a substrate, an n-type semiconductor, a quantum well, and a p-type semiconductor arranged sequentially from bottom to top. The quantum well is a periodic structure composed of a well layer and a barrier layer. A p-type contact layer is disposed above the p-type semiconductor. The p-type contact layer has saturated electron drift velocity distribution characteristics, light hole effective mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics.

[0006] The saturated electron drift velocity of the p-type contact layer exhibits an inverted N-type distribution.

[0007] The effective mass of light holes in the p-type contact layer exhibits an N-type distribution.

[0008] The deformation potential of the p-type contact layer is distributed in an N-type pattern.

[0009] The polarization optical phonon energy of the p-type contact layer exhibits an N-type distribution.

[0010] The angle at which the valley of the saturated electron drift velocity of the p-type contact layer rises towards the quantum well is: The peak position of the effective mass of light holes in the p-type contact layer decreases towards the quantum well at an angle β, the peak position of the deformation potential of the p-type contact layer decreases towards the quantum well at an angle γ, and the peak position of the polarized optical phonon energy of the p-type contact layer decreases towards the quantum well at an angle θ, wherein:

[0011] Preferably, the saturated electron drift rate of the p-type semiconductor is less than or equal to the saturated electron drift rate of the p-type contact layer and less than or equal to the saturated electron drift rate of the quantum well's well layer.

[0012] Preferably, the effective mass of light holes in the quantum well's well layer is less than or equal to the effective mass of light holes in the p-type contact layer and less than or equal to the effective mass of light holes in the p-type semiconductor.

[0013] Preferably, the deformation potential of the quantum well layer is less than or equal to the deformation potential of the p-type contact layer and less than or equal to the deformation potential of the p-type semiconductor.

[0014] Preferably, the polarization optical phonon energy of the quantum well's well layer is ≤ the polarization optical phonon energy of the p-type contact layer is ≤ the polarization optical phonon energy of the p-type semiconductor.

[0015] Preferably, the p-type contact layer is any one or any combination of GaN, AlInGaN, AlGaN, InGaN, AlN, InN, and AlInN.

[0016] Preferably, the number of periods of the quantum well is 1 to 50, and the quantum well is any one or any combination of GaN, InGaN, InN, AlInN, AlN, AlInGaN, AlGaN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, InGaP, SiC, Ga2O3, BN, and diamond. The thickness of the well layer of the quantum well is 5 angstroms to 200 angstroms, and the thickness of the barrier layer is 10 angstroms to 500 angstroms.

[0017] Preferably, the n-type semiconductor is 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, and the thickness of the n-type semiconductor is from 50 angstroms to 90,000 angstroms.

[0018] Preferably, the p-type semiconductor is 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, and the thickness of the p-type semiconductor is from 10 angstroms to 80,000 angstroms.

[0019] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, Mo, diamond, Cu, TiW, InP, or sapphire / SiO2 / SiN. x Composite substrate, sapphire / SiN x / SiO2 composite substrate, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

[0020] The beneficial effects of this invention are as follows: This invention provides a p-type contact layer above the p-type semiconductor of a nitride semiconductor light-emitting diode, and the p-type contact layer has saturated electron drift velocity distribution characteristics, light hole effective mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics, thereby enhancing hole transport and conduction in the p-type contact layer, improving the lateral and longitudinal expansion capabilities of the holes in the p-type contact layer, improving the surge capability and resistance to human body mode electrostatic breakdown of the light-emitting diode, and increasing the resistance to human body mode electrostatic breakdown from a pass rate of over 90% for 100-200V to a pass rate of over 90% for 200-500V. Attached Figure Description

[0021] 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:

[0022] Figure 1This is a schematic diagram of the structure of the nitride semiconductor light-emitting diode according to an embodiment of the present invention;

[0023] Figure 2 The SIMS secondary ion mass spectrum of the nitride semiconductor light-emitting diode described in this embodiment of the invention;

[0024] Figure 3 This is a schematic diagram of another structure of the nitride semiconductor light-emitting diode described in an embodiment of the present invention.

[0025] Figure label:

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

[0027] 102a, first sub-quantum well; 102b, second sub-quantum well; 102c, third sub-quantum well. 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] like Figure 1 and Figure 2 As shown, this embodiment proposes a nitride semiconductor light-emitting diode, which includes a substrate 100, an n-type semiconductor 101, a quantum well 102 and a p-type semiconductor 103 arranged sequentially from bottom to top, wherein a p-type contact layer 104 is disposed above the p-type semiconductor 103.

[0030] Specifically, in this embodiment, the nitride semiconductor light-emitting diode is provided with a substrate 100, an n-type semiconductor 101, a quantum well 102, and a p-type semiconductor 103 sequentially from bottom to top. A p-type contact layer 104 is disposed above the p-type semiconductor 103. The p-type contact layer 104 can be any one or any combination of GaN, AlInGaN, AlGaN, InGaN, AlN, InN, and AlInN. The p-type contact layer 104 has certain parameter distribution characteristics, specifically including saturated electron drift velocity distribution characteristics, light hole effective mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics.

[0031] The saturation electron drift rate is the overall electron drift velocity that is directly proportional to the magnitude of the electric field when the electric field is relatively low. When the electric field reaches a certain value, the overall electron drift velocity will not increase further, reaching saturation. This velocity is called the saturation electron drift rate. The saturation electron drift rate determines the upper limit of the electron drift velocity.

[0032] The effective hole mass refers to the mass characteristic of hole movement in a semiconductor material, and it is crucial for understanding the electronic structure and performance of semiconductor materials. The effective hole mass is a positive constant mp*, which is equal in magnitude but opposite in sign to the effective electron mass mn* of the empty state near the valence band apex, i.e., mp* = -mn*. The effective hole mass is calculated according to semiconductor theory. Taking a negative sign yields a hole with a larger effective mass, called a heavy hole. Taking a positive sign yields a hole with a smaller effective mass, called a light hole. The effective hole mass determines the migration ability of charge carriers in the semiconductor. A smaller effective hole mass means that holes can move more freely in the crystal lattice, thereby improving electron mobility and device conductivity.

[0033] Deformation potential describes the change of band energy with volume.

[0034] Polarized optical phonon energy: Optical phonons are tiny sound waves capable of generating powerful energy, which can be used to analyze the physical properties of metals, glasses, nanostructures, and a wide range of other materials. Optical phonons are vibrational waves generated in a medium by an electric field. They are formed by the electrically driven vibrations of ions within the medium.

[0035] Based on the characteristics of the saturated electron drift velocity, effective mass of light holes, deformation potential, and polarized optical phonon energy mentioned above, this embodiment designs the distribution of saturated electron drift velocity, effective mass of light holes, deformation potential, and polarized optical phonon energy in the p-type contact layer 104, specifically as follows:

[0036] (1) Saturated electron drift velocity distribution

[0037] The saturated electron drift velocity of the p-type contact layer 104 exhibits an inverted N-type distribution;

[0038] (2) Effective mass distribution of light cavities

[0039] The effective mass of light holes in the p-type contact layer 104 exhibits an N-type distribution.

[0040] (3) Distribution of deformation potential

[0041] The deformation potential of the p-type contact layer 104 is distributed in an N-type pattern;

[0042] (4) Polarized optical phonon energy distribution

[0043] The polarization optical phonon energy of the p-type contact layer 104 exhibits an N-type distribution.

[0044] In this embodiment, a p-type contact layer 104 is disposed above the p-type semiconductor 103 of the nitride semiconductor light-emitting diode. The p-type contact layer 104 has saturated electron drift velocity distribution characteristics, light hole effective mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics, thereby enhancing the hole transport and operation of the p-type contact layer 104, improving the lateral and longitudinal expansion capabilities of the holes in the p-type contact layer 104, improving the surge capability and resistance to human body mode electrostatic discharge (ESD) of the light-emitting diode, and increasing the ESD resistance from over 90% for 100-200V to over 90% for 200-500V.

[0045] Furthermore, in this embodiment, the saturated electron drift velocity, effective mass of light holes, deformation potential, and polarization optical phonon energy of the p-type contact layer 104 exhibit a certain angular change in the direction towards the quantum well 102, specifically as follows:

[0046] The valley position of the saturated electron drift velocity of the p-type contact layer 104 rises at an angle toward the quantum well 102.

[0047] The peak position of the effective mass of light holes in the p-type contact layer 104 decreases at a downward angle toward the quantum well 102.

[0048] The peak position of the deformation potential of the p-type contact layer 104 decreases at an angle toward the quantum well 102;

[0049] The peak position of the polarized optical phonon energy of the p-type contact layer 104 decreases at an angle toward the quantum well 102;

[0050] Specifically, the angle at which the valley of the saturated electron drift velocity of the p-type contact layer 104 rises toward the quantum well 102 is... The peak position of the effective mass of light holes in the p-type contact layer 104 decreases by an angle β towards the quantum well 102; the peak position of the deformation potential of the p-type contact layer 104 decreases by an angle γ towards the quantum well 102; and the peak position of the polarized optical phonon energy of the p-type contact layer 104 decreases by an angle θ towards the quantum well 102, where:

[0051] In some alternative embodiments, the quantum well 102 is a periodic structure consisting of a well layer and a barrier layer. The number of periods in the quantum well 102 is from 1 to 50. The quantum well 102 is any one or any combination of GaN, InGaN, InN, AlInN, AlN, AlInGaN, AlGaN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, InGaP, SiC, Ga2O3, BN, and diamond. The thickness of the well layer in the quantum well 102 is from 5 angstroms to 200 angstroms, and the thickness of the barrier layer is from 10 angstroms to 500 angstroms.

[0052] Furthermore, the quantum well 102 and the p-type semiconductor 103 also possess saturated electron drift velocity, effective light hole mass, deformation potential, and polarized optical phonon energy characteristics. These characteristics are also related to the saturated electron drift velocity, effective light hole mass, deformation potential, and polarized optical phonon energy characteristics in the p-type contact layer 104, specifically as follows:

[0053] (1) Saturated electron drift rate

[0054] The saturated electron drift rate of the p-type semiconductor 103 is less than or equal to the saturated electron drift rate of the p-type contact layer 104 and the saturated electron drift rate of the well layer of the quantum well 102.

[0055] (2) Effective mass of light cavities

[0056] The effective mass of light holes in the well layer of quantum well 102 is less than or equal to the effective mass of light holes in p-type contact layer 104 and less than or equal to the effective mass of light holes in p-type semiconductor 103.

[0057] (3) Deformation potential

[0058] The deformation potential of the quantum well 102 well layer is less than or equal to the deformation potential of the p-type contact layer 104 and the deformation potential of the p-type semiconductor 103.

[0059] (4) Polarized optical phonon energy

[0060] The polarized optical phonon energy of the well layer of quantum well 102 is less than or equal to the polarized optical phonon energy of the p-type contact layer 104 and the polarized optical phonon energy of the p-type semiconductor 103.

[0061] In some alternative embodiments, such as Figure 3As shown, the quantum well 102 includes a first sub-quantum well 102a, a second sub-quantum well 102b, and a third sub-quantum well 102c arranged sequentially from bottom to top. The first sub-quantum well 102a, the second sub-quantum well 102b, and the third sub-quantum well 102c are all periodic structures composed of well layers and barrier layers.

[0062] In some alternative embodiments, the n-type semiconductor 101 is 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, and the thickness of the n-type semiconductor 101 is from 50 angstroms to 90,000 angstroms.

[0063] In some alternative embodiments, the p-type semiconductor 103 is 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, and the thickness of the p-type semiconductor 103 is from 10 angstroms to 80,000 angstroms.

[0064] In some alternative embodiments, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, Mo, diamond, Cu, TiW, InP, sapphire / SiO2 / SiN. x Composite substrate, sapphire / SiN x / SiO2 composite substrate, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

[0065] 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 nitride semiconductor light-emitting diode, comprising, from bottom to top, a substrate, an n-type semiconductor, a quantum well, and a p-type semiconductor, wherein the quantum well is a periodic structure composed of a well layer and a barrier layer, characterized in that, A p-type contact layer is disposed above the p-type semiconductor. The p-type contact layer has saturated electron drift velocity distribution characteristics, light hole effective mass distribution characteristics, deformation potential distribution characteristics, and polarized optical phonon energy distribution characteristics. The saturated electron drift velocity of the p-type contact layer exhibits an inverted N-type distribution. The effective mass of light holes in the p-type contact layer exhibits an N-type distribution. The deformation potential of the p-type contact layer is distributed in an N-type pattern. The polarization optical phonon energy of the p-type contact layer exhibits an N-type distribution. The angle at which the valley of the saturated electron drift velocity of the p-type contact layer rises towards the quantum well is: The peak position of the effective mass of light holes in the p-type contact layer decreases towards the quantum well at an angle β, the peak position of the deformation potential of the p-type contact layer decreases towards the quantum well at an angle γ, and the peak position of the polarized optical phonon energy of the p-type contact layer decreases towards the quantum well at an angle θ, wherein:

2. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The saturated electron drift rate of a p-type semiconductor is less than or equal to the saturated electron drift rate of the p-type contact layer, which is less than or equal to the saturated electron drift rate of the well layer of a quantum well.

3. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The effective mass of light holes in the quantum well's well layer is less than or equal to the effective mass of light holes in the p-type contact layer, which is less than or equal to the effective mass of light holes in the p-type semiconductor.

4. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The deformation potential of the quantum well layer is less than or equal to the deformation potential of the p-type contact layer and less than or equal to the deformation potential of the p-type semiconductor.

5. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The polarization optical phonon energy of the quantum well's well layer is less than or equal to the polarization optical phonon energy of the p-type contact layer, which is less than or equal to the polarization optical phonon energy of the p-type semiconductor.

6. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The p-type contact layer is any one or any combination of GaN, AlInGaN, AlGaN, InGaN, AlN, InN, and AlInN.

7. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The quantum well has a period number of 1 to 50, and the quantum well is any one or any combination of GaN, InGaN, InN, AlInN, AlN, AlInGaN, AlGaN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, InGaP, SiC, Ga2O3, BN, and diamond. The thickness of the quantum well layer is 5 angstroms to 200 angstroms, and the thickness of the barrier layer is 10 angstroms to 500 angstroms.

8. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The n-type semiconductor is 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, and the thickness of the n-type semiconductor is from 50 angstroms to 90,000 angstroms.

9. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The p-type semiconductor is 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, and the thickness of the p-type semiconductor is from 10 angstroms to 80,000 angstroms.

10. The nitride semiconductor light-emitting diode according to claim 1, characterized in that, The substrate includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, Mo, diamond, Cu, TiW, InP, and sapphire / SiO2 / SiN. x Composite substrate, sapphire / SiN x / SiO2 composite substrate, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x Any one of the following composite substrates: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2.

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