A semiconductor light-emitting element with three-dimensional polar domain multiple quantum wells

Abstract

The present invention relates to the technical field of semiconductor optoelectronic devices, and in particular to a semiconductor light-emitting element with a three-dimensional polar domain multi-quantum well, which comprises, from bottom to top, a substrate, a first conductive semiconductor, a multi-quantum well and a second conductive semiconductor, wherein the multi-quantum well has a three-dimensional polar domain to form a three-dimensional polar domain quantum well; the three-dimensional polar domain multi-quantum well forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through an In / Al element synchronous oscillation layer and / or an In / Al element asynchronous oscillation layer, controls carrier transition, migration and radiation recombination in three-dimensional space by regulating the polar domain ratio of metal polarity and nitrogen polarity, eliminates quantum confinement Stark effect, improves the radiation recombination efficiency of electron holes at the three-dimensional polar domain interface, realizes conversion from electron-hole radiation recombination in two-dimensional space to electron-hole radiation recombination in three-dimensional space, and improves the luminous efficiency of the semiconductor light-emitting element.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor optoelectronic devices, and in particular to a semiconductor light-emitting element with three-dimensional polar domain multi-quantum wells. Background Art

[0002] Semiconductor components, especially semiconductor light-emitting components, have a wide adjustable wavelength range of 200 to 1200nm, high luminous efficiency, energy saving and environmental protection, long life of more than 100,000 hours, small size, strong designability, etc., and have gradually replaced incandescent lamps and fluorescent lamps, and have grown into a light source for ordinary household lighting, and are widely used in new scenarios, such as indoor high-resolution display screens, outdoor display screens, mobile TV backlighting, street lights, car lights, flashlights and other application fields. Traditional nitride semiconductors are mostly grown on sapphire substrates. The lattice mismatch and thermal mismatch between nitride semiconductors and substrates are large, resulting in a high defect density and polarization effect, which reduces the luminous efficiency of semiconductor light-emitting components; at the same time, the nitride semiconductor structure has non-central symmetry, and a strong spontaneous polarization will be generated along the c-axis direction. The piezoelectric polarization effect generated by the superposition of the lattice mismatch causes the multi-quantum well layer to produce a strong quantum confined Stark effect, causing the band tilt and the electron-hole wave function spatial separation, reducing the radiation recombination efficiency of electrons and holes. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a semiconductor light-emitting element with a three-dimensional polar domain multi-quantum well, which includes, from bottom to top, a substrate, a first conductive semiconductor, a multi-quantum well and a second conductive semiconductor, wherein the multi-quantum well has a three-dimensional polar domain to form a three-dimensional polar domain quantum well; the three-dimensional polar domain multi-quantum well forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through an In / Al element synchronous oscillation layer and / or an In / Al element asynchronous oscillation layer, and controls the ratio of polar domains of metal polarity and nitrogen polarity to control carrier transition, migration and radiation recombination in three-dimensional space, eliminates the quantum confinement Stark effect, improves the radiation recombination efficiency of electrons and holes at the three-dimensional polar domain interface, realizes the conversion from electron-hole radiation recombination in two-dimensional space to electron-hole radiation recombination in three-dimensional space, and improves the luminous efficiency of the semiconductor light-emitting element.

[0004] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0005] A semiconductor light-emitting element with a three-dimensional polar domain multi-quantum well comprises, from bottom to top, a substrate, a first conductive semiconductor, a multi-quantum well and a second conductive semiconductor, wherein the multi-quantum well has a three-dimensional polar domain to form a three-dimensional polar domain quantum well.

[0006] In the above technical scheme, the three-dimensional polar domain multiple quantum well includes any one or any combination of In / Al element synchronous oscillation layers and / or In / Al element asynchronous oscillation layers, and a composite three-dimensional polar domain multiple quantum well with metal polarity and nitrogen polarity is formed through the alternating growth of In / Al element synchronous oscillation layers and / or In / Al element asynchronous oscillation layers.

[0007] In the above technical scheme, the three-dimensional polar domain multiple quantum well forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer. By adjusting the polar domain ratio of metal polarity and nitrogen polarity, the carrier transition, migration and radiation recombination in three-dimensional space are controlled, the quantum confined Stark effect is eliminated, the radiation recombination efficiency of electrons and holes at the three-dimensional polar domain interface is improved, the conversion from electron-hole radiation recombination in two-dimensional space to electron-hole radiation recombination in three-dimensional space is realized, and the luminescence efficiency of semiconductor light-emitting elements is improved.

[0008] In the above technical solution, the oscillations of In and Al elements of the three-dimensional polar domain multi-quantum well are calibrated by SIMS testing. The In element of the In / Al element synchronous oscillation layer oscillates in the range of 1E3 to 1E6 c / s, and the Al element oscillates in the range of 1E3 to 1E6 c / s; the In element of the In / Al element asynchronous oscillation layer oscillates in the range of 1E2 to 1E5 c / s, and the Al element gradually increases or decreases in the range of 1E1 to 5E4 c / s or remains constant without oscillation.

[0009] In the above technical solution, the concentrations of C, O and Si elements in the three-dimensional polar domain multi-quantum well are calibrated by SIMS (secondary ion mass spectrometer) test (unit: atoms / cm 3 ), the C element concentration is 1E16~5E17 atoms / cm 3 , O element concentration is 1E16~1E18 atoms / cm 3 , Si element concentration is 1E17~1E19 atoms / cm 3 .

[0010] In the above technical scheme, the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer of the three-dimensional polar domain multiple quantum well are matched with the C, O, and Si element concentrations in a specific range, which can realize the Fermi level gradient change of the polar domain multiple quantum well, form a lateral space charge region, enhance the quantum localization effect of electron-hole carriers in the three-dimensional polar domain multiple quantum well, reduce the quantum confinement Stark effect, realize electron-hole recombination in three-dimensional space, and further improve the electron-hole radiation recombination efficiency.

[0011] In the above technical scheme, the three-dimensional polar domain multiple quantum well includes any one or any multiple combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP.

[0012] In the above technical solution, the number of periods of the three-dimensional polar domain multi-quantum well is 1 to 50 periods.

[0013] In the above technical scheme, the first conductive type semiconductor and the second conductive type semiconductor include any one or any multiple combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP.

[0014] In the above technical scheme, the substrate includes any one of sapphire, silicon, Ge, SiC, AlN, 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.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention aims at the problem of strong quantum confinement Stark effect in the traditional multi-quantum well layer, based on the relationship between the polarization electric field and the components in the quantum well, controls the polarization electric field in the quantum well by designing the oscillation frequency of the components, and forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer, such as Figure 3 As shown, preferably, by regulating the polar domain ratio of metal polarity and nitrogen polarity, controlling the carrier transition, migration and radiative recombination in three-dimensional space, eliminating the quantum confinement Stark effect, improving the radiative recombination efficiency of electron holes at the three-dimensional polar domain interface, realizing the conversion from electron-hole radiative recombination in two-dimensional space to electron-hole radiative recombination in three-dimensional space, and improving the luminous efficiency of semiconductor light-emitting elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of a semiconductor light-emitting element having a three-dimensional polar domain multi-quantum well according to an embodiment of the present invention;

[0017] Figure 2It is a SIMS secondary ion mass spectrum of a semiconductor light-emitting element with three-dimensional polar domain multiple quantum wells according to an embodiment of the present invention;

[0018] Figure 3 This is a TEM transmission electron microscope image of a semiconductor light-emitting element having a three-dimensional polar domain multi-quantum well according to an embodiment of the present invention;

[0019] Reference numerals: 100: substrate; 101: first conductive type semiconductor, 102: three-dimensional polar domain multiple quantum well, 102a: In / Al element asynchronous oscillation layer, 102b: In / Al element synchronous oscillation layer, 103: second conductive type semiconductor. DETAILED DESCRIPTION

[0020] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0021] like Figure 1 As shown, a semiconductor light-emitting element with a three-dimensional polar domain multi-quantum well according to Embodiment 1 of the present invention comprises, from bottom to top, a substrate 100, a first conductive semiconductor 101, a multi-quantum well 102, and a second conductive semiconductor 103. The substrate 100 is a substrate on which nitride semiconductor crystals can be epitaxially grown, and a substrate having a high transmittance (for example, a transmittance of the light being above 50%) in the wavelength range of light emitted by the semiconductor light-emitting element can be selected and used; the first conductive semiconductor 101 and the second conductive semiconductor 103 can be An n-type semiconductor layer with an n-type conductivity type; or a p-type semiconductor layer with a p-type conductivity type; a first conductive semiconductor 101, a multiple quantum well 102, and a second conductive semiconductor 103 are sequentially stacked on a substrate 100, and the stacked semiconductor layers are stacked using methods such as organic metal chemical vapor deposition (MOCVD), organic metal vapor phase epitaxy (MOVPE), molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE); wherein the multiple quantum well has a three-dimensional polar domain, forming a three-dimensional polar domain quantum well.

[0022] Furthermore, the three-dimensional polar domain multiple quantum well includes any one or any combination of In / Al element synchronous oscillation layer 102b and / or In / Al element asynchronous oscillation layer 102a, and a composite three-dimensional polar domain multiple quantum well of metal polarity and nitrogen polarity is formed through the alternating growth of In / Al element synchronous oscillation layer 102b and / or In / Al element asynchronous oscillation layer 102a.

[0023] Traditional nitride semiconductors are grown on sapphire substrates, which have large lattice mismatch and thermal mismatch, resulting in high defect density and polarization effect, reducing the luminous efficiency of semiconductor light-emitting elements; at the same time, the nitride semiconductor structure has non-central symmetry, and will produce strong spontaneous polarization along the c-axis direction. The superposition of the piezoelectric polarization effect of the lattice mismatch causes the multi-quantum well layer to produce a strong quantum confined Stark effect, causing energy band tilting and spatial separation of electron-hole wave functions, and reducing the radiation recombination efficiency of electrons and holes; the present invention aims at the problem of strong quantum confined Stark effect in traditional multi-quantum well layers, based on the relationship between the polarization electric field and the components in the quantum well, controls the polarization electric field in the quantum well by designing the oscillation frequency of the components, and forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer, such as Figure 3 As shown, preferably, by regulating the polar domain ratio of metal polarity and nitrogen polarity, controlling the carrier transition, migration and radiative recombination in three-dimensional space, eliminating the quantum confinement Stark effect, improving the radiative recombination efficiency of electron holes at the three-dimensional polar domain interface, realizing the conversion from electron-hole radiative recombination in two-dimensional space to electron-hole radiative recombination in three-dimensional space, and improving the luminous efficiency of semiconductor light-emitting elements.

[0024] Figure 2 It is a SIMS secondary ion mass spectrum of a semiconductor light-emitting element with a three-dimensional polar domain multiple quantum well in an embodiment of the present invention. The oscillation of In and Al elements in the three-dimensional polar domain multiple quantum well is tested and calibrated by SIMS (secondary ion mass spectrometer) (the unit of element test intensity is c / s). Preferably, the In element of the In / Al element synchronous oscillation layer oscillates in the range of 1E3 to 1E6 c / s, and the Al element oscillates in the range of 1E3 to 1E6 c / s; the In element of the In / Al element asynchronous oscillation layer oscillates in the range of 1E2 to 1E5 c / s, and the Al element gradually increases or decreases in the range of 1E1 to 5E4 c / s or remains constant without oscillation.

[0025] As an improvement of the technical solution of the present invention, the C element concentration of the multi-quantum well is 1E 16 to 5E17 atoms / cm 3 , O element concentration is 1E 16~1E18 atoms / cm 3 , Si element concentration is 1E 17~1E19atoms / cm 3 The concentrations of C, O, and Si in the three-dimensional polar domain multi-quantum wells were measured and calibrated by SIMS (secondary ion mass spectrometry) (unit: atoms / cm 3), the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer of the three-dimensional polar domain multi-quantum well are matched with the C, O, and Si element concentrations in a specific range, which can realize the Fermi level gradient change of the polar domain multi-quantum well, form a lateral space charge region, enhance the quantum localization effect of the electron-hole carriers in the three-dimensional polar domain multi-quantum well, reduce the quantum confinement Stark effect, realize the electron-hole recombination in the three-dimensional space, and further improve the electron-hole radiation recombination efficiency.

[0026] In the present invention, the three-dimensional polar domain multi-quantum well includes any one or any combination of two or more of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, InGaP, including but not limited to the following structures: InGaN / AlGaN, InGaN / AlInGaN, InAlGaN / GaN, InGaN / GaN, InGaN / InAlN, AlGaN / AlGaN, AlGaN / AlInGaN, AlInGaN / AlInGaN, AlInGaN / AlGaN, GaN / AlGaN, GaN / AlInGaN, AlInN / GaN, AlInN / Any one or any two or more combinations of AlGaN, AlInN / AlInGaN, InGaN / AlGaN / GaN / AlGaN / GaN, InGaN / GaN / AlGaN / GaN, InGaN / AlInGaN / GaN / AlInGaN.

[0027] The number of periods of the three-dimensional polar domain multi-quantum well is 1 to 50 periods, that is, the In / Al element synchronous oscillation layer and / or the In / Al element asynchronous oscillation layer are combined and grown alternately in any order, and the total number of periods is 1 to 50.

[0028] The first conductive type semiconductor and the second conductive type semiconductor include any one or any multiple combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP.

[0029] The substrate includes any one of sapphire, silicon, Ge, SiC, AlN, 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.

[0030] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A semiconductor light-emitting element having a three-dimensional polar domain multi-quantum well, comprising, from bottom to top, a substrate, a first conductive semiconductor, a multi-quantum well, and a second conductive semiconductor, characterized in that: The multiple quantum well has a three-dimensional polar domain to form a three-dimensional polar domain multiple quantum well; the three-dimensional polar domain multiple quantum well includes a synchronous oscillation layer of In and Al elements and an asynchronous oscillation layer of In and Al elements, and a composite three-dimensional polar domain multiple quantum well of metal polarity and nitrogen polarity is formed through the alternating growth of the synchronous oscillation layer of In and Al elements and the asynchronous oscillation layer of In and Al elements; the three-dimensional polar domain multiple quantum well forms a composite three-dimensional polar domain quantum well with metal polarity and nitrogen polarity through the synchronous oscillation layer of In and Al elements and the asynchronous oscillation layer of In and Al elements, and controls the carrier transition, migration and radiation recombination in three-dimensional space by regulating the polar domain ratio of metal polarity and nitrogen polarity, eliminates the quantum confinement Stark effect, improves the radiation recombination efficiency of electrons and holes at the three-dimensional polar domain interface, realizes the conversion from electron-hole radiation recombination in two-dimensional space to electron-hole radiation recombination in three-dimensional space, and improves the luminous efficiency of semiconductor light-emitting elements.

2. A semiconductor light emitting element having a three-dimensional polar domain multiple quantum well as claimed in claim 1, characterized in that: The oscillation of In and Al elements in the three-dimensional polar domain multi-quantum well is calibrated by SIMS testing. The In element of the In and Al element synchronous oscillation layer oscillates in the range of 1E3 to 1E6 c / s, and the Al element oscillates in the range of 1E3 to 1E6 c / s; the In element of the In and Al element asynchronous oscillation layer oscillates in the range of 1E2 to 1E5 c / s, and the Al element rises or falls or remains constant in the range of 1E1 to 5E4 c / s without oscillation.

3. A semiconductor light emitting element having a three-dimensional polar domain multi-quantum well as claimed in claim 2, characterized in that: The C, O, and Si element concentrations of the three-dimensional polar domain multi-quantum well are calibrated by SIMS testing, and the C element concentration is 1E 16 to 5E17 atoms / cm 3 , O element concentration is 1E16~1E18 atoms / cm 3 , Si element concentration is 1E17~1E19 atoms / cm 3 .

4. A semiconductor light emitting element having three-dimensional polar domain multiple quantum wells as claimed in claim 3, characterized in that: The synchronous oscillation layer of In and Al elements and the asynchronous oscillation layer of In and Al elements of the three-dimensional polar domain multiple quantum well are matched with the concentrations of C, O, and Si elements in a specific range to realize the gradient change of the Fermi level of the polar domain multiple quantum well, form a lateral space charge region, enhance the quantum localization effect of electron-hole carriers in the three-dimensional polar domain multiple quantum well, reduce the quantum confinement Stark effect, realize electron-hole recombination in three-dimensional space, and further improve the electron-hole radiation recombination efficiency.

5. A semiconductor light emitting element having three-dimensional polar domain multiple quantum wells as claimed in claim 1, characterized in that: The three-dimensional polar domain multiple quantum well includes any one or any multiple combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP.

6. A semiconductor light emitting element having three-dimensional polar domain multiple quantum wells as claimed in claim 1, characterized in that: The period number of the three-dimensional polar domain multi-quantum well is 1 to 50 periods.

7. A semiconductor light emitting element having three-dimensional polar domain multiple quantum wells as claimed in claim 1, characterized in that: The first conductive type semiconductor and the second conductive type semiconductor include any one or any multiple combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, AlInN, SiC, Ga2O3, BN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, AlInAs, AlInP, AlGaP, and InGaP.

8. A semiconductor light emitting element having three-dimensional polar domain multiple quantum wells as claimed in claim 1, characterized in that: The substrate includes any one of sapphire, silicon, Ge, SiC, AlN, 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.

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