A gallium nitride-based semiconductor laser

Abstract

This invention proposes a gallium nitride-based semiconductor laser, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer. This invention incorporates a multi-layered, multi-vacancy electron-phonon modulation layer within the semiconductor laser element, defining the electron affinity distribution and polarization optical phonon energy distribution characteristics of each multi-vacancy electron-phonon modulation layer. This forms single-vacancy, vacancy cluster, and multi-vacancy modulated electron-phonon structures, localizing electron-phonons between the lower confinement layer and the lower waveguide layer. This reduces the Stokes shift caused by the photon energy difference between the pump light and the oscillating light, reduces heat loss from phonon vibration and phonon transport, improves the heat dissipation of the laser element, mitigates interlayer thermal mismatch, suppresses the thermal lensing effect and stress birefringence effect of the laser, improves laser beam distortion and depolarization, and enhances the laser beam quality factor.

Description

Technical Field

[0001] This application relates to the field of semiconductor optoelectronic devices, and more particularly to a gallium nitride-based semiconductor laser. Background Technology

[0002] Lasers are widely used in laser displays, laser TVs, laser projectors, communications, medical applications, weaponry, guidance, ranging, spectral analysis, cutting, precision welding, and high-density optical storage. There are many types of lasers, and they can be classified in various ways, mainly including solid-state, gas, liquid, semiconductor, and dye lasers. Compared with other types of lasers, all-solid-state semiconductor lasers have advantages such as small size, high efficiency, light weight, good stability, long lifespan, simple and compact structure, and miniaturization.

[0003] Lasers and nitride semiconductor light-emitting diodes (LEDs) differ significantly:

[0004] 1) Lasers are generated by stimulated emission of charge carriers. They have a small half-width at half-maximum and very high brightness. The output power of a single laser can be in the W range. In contrast, nitride semiconductor light-emitting diodes are spontaneously emitted, and the output power of a single light-emitting diode is in the mW range.

[0005] 2) The operating current density of lasers reaches KA / cm2, which is more than two orders of magnitude higher than that of nitride light-emitting diodes. This results in stronger electron leakage, more severe Auger recombination, stronger polarization effect, and more severe electron-hole mismatch, leading to more severe efficiency degradation and the Droop effect.

[0006] 3) Light-emitting diodes emit spontaneous transition radiation, which is incoherent light that transitions from a high energy level to a low energy level without external influence. In contrast, lasers emit stimulated transition radiation, where the energy of the induced photon should be equal to the energy difference of the electron transition, producing coherent light that is identical to the induced photon.

[0007] 4) Different principles: Light emission diodes emit light by electrons and holes jumping to quantum wells or pn junctions under the action of external voltage, generating radiative recombination. Lasers, on the other hand, require certain lasing conditions to be met before they can emit light. This requires the carriers in the active region to be reversed, the stimulated emission light to oscillate back and forth in the resonant cavity, and the propagation in the gain medium to amplify the light. When the threshold condition is met, the gain is greater than the loss, and finally, laser light is output.

[0008] Nitride semiconductor lasers suffer from the following problems: Thermal loss: Stokes shift loss due to the photon energy difference between the pump light and the oscillating light is converted into heat, as is energy loss due to the non-uniform coupling ratio from the pump level to the upper laser level. Both generate a large amount of waste heat, leading to uneven temperature distribution, thermal expansion, and uneven thermal stress distribution. This results in temperature quenching, laser breakage, thermal lensing, and stress birefringence. Thermal lensing produces lens-like phenomena in space, while stress birefringence alters the polarization state of the incident light, causing depolarization and distortion of the laser beam. Non-radiative recombination loss and free carrier absorption in the active region of the laser chip generate significant heat. Simultaneously, the resistance of the epitaxial layer and chip materials under current injection generates Joule heat loss and carrier absorption loss. Furthermore, the low thermal conductivity of the chip material results in poor heat dissipation, leading to increased active layer temperature and problems such as redshift of the lasing wavelength, decreased quantum efficiency, reduced power, increased threshold current, shorter lifetime, and decreased reliability. Summary of the Invention

[0009] To address one of the aforementioned technical problems, the present invention provides a gallium nitride-based semiconductor laser.

[0010] This invention provides a gallium nitride-based semiconductor laser, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer. The lower confinement layer comprises, from bottom to top, a first lower confinement layer, a second lower confinement layer, and a third lower confinement layer. The gallium nitride-based semiconductor laser also includes a multiple vacancy electron-phonon modulation layer, comprising a first multiple vacancy electron-phonon modulation layer, a second multiple vacancy electron-phonon modulation layer, and a third multiple vacancy electron-phonon modulation layer. The first multiple vacancy electron-phonon modulation layer is disposed between the first lower confinement layer and the second lower confinement layer; the second multiple vacancy electron-phonon modulation layer is disposed between the second lower confinement layer and the third lower confinement layer; and the third multiple vacancy electron-phonon modulation layer is disposed between the third lower confinement layer and the lower waveguide layer. The first, second, and third multiple vacancy electron-phonon modulation layers all possess electron affinity distribution characteristics and polarized optical phonon energy distribution characteristics.

[0011] The electron affinity of the first multi-vacancy electron-phonon modulation layer has the function y1 = A + B*e x1 / x1 Third quadrant curve distribution; the electron affinity of the second multi-vacancy electron-phonon modulation layer has a function y2=C+D*lnx2 / x2 curve distribution; the electron affinity of the third multi-vacancy electron-phonon modulation layer has a function y3=E+F*x3 / lnx3 First quadrant curve distribution;

[0012] The polarization optical phonon energy of the first multi-vacancy electron phonon modulation layer has the function y4=M+N*lnx1 / e x1 Curve distribution; the polarized optical phonon energy of the second multi-vacancy electron-phonon modulation layer has the function y5=O+P*e x2 / x2 Third Quadrant Curve Distribution; The polarized optical phonon energy of the third multi-vacancy electron-phonon modulation layer has the function y6=Q+R*x3 / e x3 Curve distribution;

[0013] Where x1 is the depth of the first multi-vacancy electron-phonon modulation layer toward the second lower confinement layer, x2 is the depth of the second multi-vacancy electron-phonon modulation layer toward the third lower confinement layer, and x3 is the depth of the third multi-vacancy electron-phonon modulation layer toward the lower waveguide layer.

[0014] Preferably, the electron affinity of the first multi-vacancy electron-phonon modulation layer is d, the electron affinity of the second multi-vacancy electron-phonon modulation layer is e, and the electron affinity of the third multi-vacancy electron-phonon modulation layer is f, where: 0.1 < f < e < d < 10.

[0015] Preferably, the polarized optical phonon energy of the first multi-vacancy electron-phonon modulation layer is j, the polarized optical phonon energy of the second multi-vacancy electron-phonon modulation layer is k, and the polarized optical phonon energy of the third multi-vacancy electron-phonon modulation layer is l, wherein: 30 (meV) < j < l < k < 800 (meV).

[0016] Preferably, the first, second, and third multiple vacancy electron-phonon modulation layers also have electron effective mass distribution characteristics and dielectric constant distribution characteristics.

[0017] The effective electron mass of the first multi-vacancy electron-phonon modulation layer has a curve distribution of function y7 = G + H * lnx1 / x1; the effective electron mass of the second multi-vacancy electron-phonon modulation layer has a curve distribution of function y8 = I + J * x2 / lnx2 in the third quadrant; and the effective electron mass of the third multi-vacancy electron-phonon modulation layer has a curve distribution of function y9 = K + L * lnx3 / x3.

[0018] The dielectric constant of the first multi-vacancy electron phonon modulation layer has a function y 10 =S+T*cosx1 / x1 Second quadrant curve distribution; the dielectric constant of the second multi-vacancy electron-phonon modulation layer has a function y 11 =U+V*x2 / e x2 Curve distribution; the dielectric constant of the third multi-vacancy electron-phonon modulation layer has a function y 12=W + Z * sinx³ / x³ 2 The curve distribution in the first quadrant.

[0019] Preferably, the effective electron mass of the first multi-vacancy electron-phonon modulation layer is g, the effective electron mass of the second multi-vacancy electron-phonon modulation layer is h, and the effective electron mass of the third multi-vacancy electron-phonon modulation layer is i, wherein: 0.01 < g < i < h < 5.

[0020] Preferably, the dielectric constant of the first multi-vacancy electron-phonon modulation layer is m, the dielectric constant of the second multi-vacancy electron-phonon modulation layer is n, and the dielectric constant of the third multi-vacancy electron-phonon modulation layer is p, where: 2 < n < p < m < 20.

[0021] Preferably, the multiple vacancy electron phonon modulation layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and diamond.

[0022] Preferably, the active layer is a periodic structure composed of a well layer and a barrier layer, and the number of periods is 3≥m≥1;

[0023] The well layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 100 angstroms.

[0024] The barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 200 angstroms.

[0025] Preferably, the lower confinement layer, lower waveguide layer, upper waveguide layer, and upper confinement layer are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN.

[0026] Preferably, the substrate comprises sapphire, silicon, CuW, Mo, TiW, Cu, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x Sapphire / SiO2 / SiN x The composite substrate, or any one of the following: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2 composite substrate.

[0027] The beneficial effects of this invention are as follows: This invention sets up a multi-layered multi-vacancy electron-phonon modulation layer in a semiconductor laser element, and intersperses the multi-layered multi-vacancy electron-phonon modulation layer in multiple lower confinement layers. At the same time, it limits the electron affinity distribution characteristics and polarization optical phonon energy distribution characteristics of each multi-vacancy electron-phonon modulation layer to form a single-vacancy, vacancy cluster, and multi-vacancy modulated electron-phonon structure. This localizes electron-phonons between the lower confinement layer and the lower waveguide layer, reduces the Stokes frequency shift caused by the photon energy difference between the pump light and the oscillating light, reduces the heat loss of phonon vibration and phonon transport, improves the heat dissipation of the laser element and improves the thermal mismatch between epitaxial layers, suppresses the thermal lensing effect and stress birefringence effect of the laser, improves the laser beam distortion and depolarization problems, and improves the laser beam quality factor. Attached Figure Description

[0028] 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:

[0029] Figure 1 This is a schematic diagram of the structure of the gallium nitride-based semiconductor laser according to an embodiment of the present invention;

[0030] Figure 2 This is a SIMS secondary ion mass spectrum of the gallium nitride-based semiconductor laser described in an embodiment of the present invention.

[0031] Figure label:

[0032] 100. Substrate; 101. Lower confinement layer; 102. Lower waveguide layer; 103. Active layer; 104. Upper waveguide layer; 105. Upper confinement layer; 106. Multiple vacancy electron-phonon modulation layer.

[0033] 101a, First lower confinement layer; 101b, Second lower confinement layer; 101c, Third lower confinement layer;

[0034] 106a, First multi-vacancy electron-phonon control layer; 106b, Second multi-vacancy electron-phonon control layer; 106c, Third multi-vacancy electron-phonon control layer. Detailed Implementation

[0035] 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.

[0036] like Figure 1 and Figure 2 As shown, this embodiment proposes a gallium nitride-based semiconductor laser, comprising a substrate 100, a lower confinement layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104, and an upper confinement layer 105 arranged sequentially from bottom to top. A multi-vacancy electron-phonon modulation layer 106 is also provided in this gallium nitride-based semiconductor laser.

[0037] Specifically, in this embodiment, the gallium nitride-based semiconductor laser is provided with, from bottom to top, a substrate 100, a lower confinement layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104, and an upper confinement layer 105. The lower confinement layer 101 has a multilayer structure, including a first lower confinement layer 101a, a second lower confinement layer 101b, and a third lower confinement layer 101c, which are arranged sequentially from bottom to top. A multiple vacancy electron phonon modulation layer 106 is also provided in the semiconductor laser element. The multiple vacancy electron-phonon modulation layer 106 is also a multilayer structure, including a first multiple vacancy electron-phonon modulation layer 106a, a second multiple vacancy electron-phonon modulation layer 106b, and a third multiple vacancy electron-phonon modulation layer 106c. These three layers are interleaved between the first lower confinement layer 101a, the second lower confinement layer 101b, and the third lower confinement layer 101c. Specifically, the first multiple vacancy electron-phonon modulation layer 106a is disposed between the first lower confinement layer and the second lower confinement layer 101b; the second multiple vacancy electron-phonon modulation layer 106b is disposed between the second lower confinement layer 101b and the third lower confinement layer 101c; and the third multiple vacancy electron-phonon modulation layer 106c is disposed between the third lower confinement layer 101c and the lower waveguide layer 102.

[0038] In this multi-layered multi-vacancy electron-phonon modulation layer 106, the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c all possess electron affinity distribution characteristics and polarized optical phonon energy distribution characteristics, as specifically shown below:

[0039] Electron affinity distribution:

[0040] The electron affinity of the first multivacancy electron-phonon modulation layer 106a has the function y1 = A + B*e. x1 / x1 Third Quadrant Curve Distribution;

[0041] The electron affinity of the second multivacancy electron-phonon modulation layer 106b has a function y2=C+D*lnx2 / x2 curve distribution;

[0042] The electron affinity of the third multivacancy electron-phonon modulation layer 106c has a first quadrant curve distribution of the function y3=E+F*x3 / lnx3;

[0043] Polarized optical phonon energy distribution:

[0044] The polarized optical phonon energy of the first multi-vacancy electron-phonon modulation layer 106a has the function y4=M+N*lnx1 / e x1 Curve distribution;

[0045] The polarization optical phonon energy of the second multivacancy electron phonon modulation layer 106b has the function y5=O+P*e x2 / x2 Third Quadrant Curve Distribution;

[0046] The polarized optical phonon energy of the third multi-vacancy electron-phonon modulation layer 106c has the function y6=Q+R*x3 / e x3 Curve distribution;

[0047] Where x1 is the depth of the first multi-vacancy electron-phonon modulation layer 106a toward the second lower confinement layer 101b, x2 is the depth of the second multi-vacancy electron-phonon modulation layer 106b toward the third lower confinement layer 101c, and x3 is the depth of the third multi-vacancy electron-phonon modulation layer 106c toward the lower waveguide layer 102.

[0048] In this embodiment, a multi-layered multi-vacancy electron-phonon modulation layer 106 is provided in the semiconductor laser element, and the multi-layered multi-vacancy electron-phonon modulation layer 106 is interspersed in the multi-layered lower confinement layer 101. At the same time, the electron affinity distribution characteristics and polarization optical phonon energy distribution characteristics of each multi-vacancy electron-phonon modulation layer 106 are defined to form a single-vacancy, vacancy cluster and multi-vacancy modulated electron-phonon structure. The electron-phonons are localized between the lower confinement layer and the lower waveguide layer, reducing the Stokes frequency shift caused by the photon energy difference between the pump light and the oscillating light, reducing the heat loss of phonon vibration and phonon transport, improving the heat dissipation of the laser element and improving the thermal mismatch between epitaxial layers, suppressing the thermal lensing effect and stress birefringence effect of the laser, improving the laser beam distortion and depolarization problem, and improving the laser beam quality factor.

[0049] In some optional embodiments, the electron affinity in the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c also has the following relationship:

[0050] The electron affinity of the first multivacancy electron-phonon modulation layer 106a is d, the electron affinity of the second multivacancy electron-phonon modulation layer 106b is e, and the electron affinity of the third multivacancy electron-phonon modulation layer 106c is f, where: 0.1 < f < e < d < 10.

[0051] In some optional embodiments, the polarization optical phonon energies in the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c also have the following relationship:

[0052] The polarized optical phonon energy of the first multi-vacancy electron-phonon control layer 106a is j, the polarized optical phonon energy of the second multi-vacancy electron-phonon control layer 106b is k, and the polarized optical phonon energy of the third multi-vacancy electron-phonon control layer 106c is l, where: 30 (meV) < j < l < k < 800 (meV).

[0053] In some optional embodiments, the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c also possess electron effective mass distribution characteristics and dielectric constant distribution characteristics, specifically manifested as follows:

[0054] Effective electron mass distribution:

[0055] The effective electron mass of the first multi-vacancy electron phonon control layer 106a has a function y7=G+H*lnx1 / x1 curve distribution;

[0056] The effective electron mass of the second multivacancy electron-phonon control layer 106b has a third quadrant curve distribution of the function y8=I+J*x2 / lnx2;

[0057] The effective electron mass of the third multivacancy electron-phonon control layer 106c has a function y9 = K + L*lnx3 / x3 curve distribution;

[0058] Dielectric constant distribution:

[0059] The dielectric constant of the first multi-vacancy electron-phonon modulation layer 106a has a function y 10 =S + T * cosx1 / x1 Distribution of the second and fourth quadrant curves;

[0060] The dielectric constant of the second multi-vacancy electron-phonon modulation layer 106b has a function y 11 =U+V*x2 / e x2 Curve distribution;

[0061] The dielectric constant of the third multi-vacancy electron-phonon modulation layer 106c has a function y 12 =W + Z * sinx³ / x³ 2 The curve distribution in the first quadrant.

[0062] By limiting the effective electron mass distribution and dielectric constant distribution in each multi-vacancy electron-phonon modulation layer 106, it is possible to improve electron-hole transport efficiency, reduce non-radiative recombination loss and free carrier absorption loss, improve the heat dissipation capacity of the laser, reduce heat accumulation, Joule heat loss and carrier absorption loss in the active layer, lower the temperature of the active layer, improve quantum efficiency and reduce threshold current, and improve problems such as increased active layer temperature, decreased quantum efficiency, increased threshold current and deteriorated reliability.

[0063] In some optional embodiments, the effective electron masses in the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c also have the following relationship:

[0064] The effective electron mass of the first multi-vacancy electron-phonon control layer 106a is g, the effective electron mass of the second multi-vacancy electron-phonon control layer 106b is h, and the effective electron mass of the third multi-vacancy electron-phonon control layer 106c is i, where: 0.01 < g < i < h < 5.

[0065] In some optional embodiments, the dielectric constants of the first multi-vacancy electron-phonon modulation layer 106a, the second multi-vacancy electron-phonon modulation layer 106b, and the third multi-vacancy electron-phonon modulation layer 106c also have the following relationship:

[0066] The dielectric constant of the first multi-vacancy electron-phonon modulation layer 106a is m, the dielectric constant of the second multi-vacancy electron-phonon modulation layer 106b is n, and the dielectric constant of the third multi-vacancy electron-phonon modulation layer 106c is p, where: 2 < n < p < m < 20.

[0067] In some alternative embodiments, the multiple vacancy electron phonon control layer 106 is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and diamond.

[0068] In some alternative embodiments, the active layer 103 is a periodic structure composed of a well layer and a barrier layer, with a period number of 3 ≥ m ≥ 1.

[0069] Specifically, the well layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 100 angstroms.

[0070] The barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 200 angstroms.

[0071] In some optional embodiments, the lower confinement layer 101, the lower waveguide layer 102, the upper waveguide layer 104, and the upper confinement layer 105 are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN.

[0072] In some alternative embodiments, the substrate 100 includes sapphire, silicon, CuW, Mo, TiW, Cu, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, and sapphire / SiN composite substrate. x Sapphire / SiO2 / SiN x The composite substrate, or any one of the following: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2 composite substrate.

[0073] The table below compares the parameters of a conventional semiconductor laser device with the gallium nitride-based semiconductor laser proposed in this embodiment, including beam quality factor, threshold current density, and optical power, highlighting the differences between the two devices.

[0074]

[0075] As can be seen, the gallium nitride-based semiconductor laser proposed in this embodiment improves the beam quality factor and optical power and reduces the threshold current density compared with traditional semiconductor laser elements, showing significant advantages over traditional semiconductor laser elements.

[0076] 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 gallium nitride-based semiconductor laser, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer, characterized in that, The lower confinement layer includes a first lower confinement layer, a second lower confinement layer, and a third lower confinement layer arranged sequentially from bottom to top. The gallium nitride-based semiconductor laser also includes a multiple vacancy electron-phonon modulation layer, which includes a first multiple vacancy electron-phonon modulation layer, a second multiple vacancy electron-phonon modulation layer, and a third multiple vacancy electron-phonon modulation layer. The first multiple vacancy electron-phonon modulation layer is disposed between the first lower confinement layer and the second lower confinement layer. The second multiple vacancy electron-phonon modulation layer is disposed between the second lower confinement layer and the third lower confinement layer. The third multiple vacancy electron-phonon modulation layer is disposed between the third lower confinement layer and the lower waveguide layer. The first multiple vacancy electron-phonon modulation layer, the second multiple vacancy electron-phonon modulation layer, and the third multiple vacancy electron-phonon modulation layer all have electron affinity distribution characteristics and polarized optical phonon energy distribution characteristics. The electron affinity of the first multi-vacancy electron-phonon modulation layer has the function y1=A+B*e x1 / x1 Third quadrant curve distribution; the electron affinity of the second multi-vacancy electron-phonon modulation layer has a function y2=C+D*lnx2 / x2 curve distribution; the electron affinity of the third multi-vacancy electron-phonon modulation layer has a function y3=E+F*x3 / lnx3 First quadrant curve distribution; The polarized optical phonon energy of the first multi-vacancy electron phonon modulation layer has the function y4=M+N*lnx1 / e x1 Curve distribution; the polarized optical phonon energy of the second multi-vacancy electron-phonon modulation layer has the function y5=O+P*e x2 / x2 Third Quadrant Curve Distribution; The polarized optical phonon energy of the third multi-vacancy electron-phonon modulation layer has the function y6=Q+R*x3 / e x3 Curve distribution; Where x1 is the depth of the first multi-vacancy electron-phonon modulation layer toward the second lower confinement layer, x2 is the depth of the second multi-vacancy electron-phonon modulation layer toward the third lower confinement layer, and x3 is the depth of the third multi-vacancy electron-phonon modulation layer toward the lower waveguide layer.

2. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The electron affinity of the first multi-vacancy electron-phonon modulation layer is d, the electron affinity of the second multi-vacancy electron-phonon modulation layer is e, and the electron affinity of the third multi-vacancy electron-phonon modulation layer is f, where: 0.1 < f < e < d < 10.

3. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The polarized optical phonon energy of the first multi-vacancy electron-phonon modulation layer is j, the polarized optical phonon energy of the second multi-vacancy electron-phonon modulation layer is k, and the polarized optical phonon energy of the third multi-vacancy electron-phonon modulation layer is l, where: 30meV < j < l < k < 800meV.

4. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The first, second, and third multiple vacancy electron-phonon modulation layers also possess electron effective mass distribution characteristics and dielectric constant distribution characteristics. The effective electron mass of the first multi-vacancy electron-phonon modulation layer has a curve distribution of function y7=G+H*lnx1 / x1; the effective electron mass of the second multi-vacancy electron-phonon modulation layer has a curve distribution of function y8=I+J*x2 / lnx2 in the third quadrant; and the effective electron mass of the third multi-vacancy electron-phonon modulation layer has a curve distribution of function y9=K+L*lnx3 / x3. The dielectric constant of the first multi-vacancy electron phonon modulation layer has a function y 10 =S+T*cosx1 / x1 Second quadrant curve distribution; The dielectric constant of the second multi-vacancy electron phonon modulation layer has a function y 11 =U+V*x2 / e x2 Curve distribution; the dielectric constant of the third multi-vacancy electron-phonon modulation layer has a function y 12 =W + Z * sinx³ / x³ 2 The curve distribution in the first quadrant.

5. The gallium nitride-based semiconductor laser according to claim 4, characterized in that, The effective electron mass of the first multi-vacancy electron-phonon modulation layer is g, the effective electron mass of the second multi-vacancy electron-phonon modulation layer is h, and the effective electron mass of the third multi-vacancy electron-phonon modulation layer is i, where: 0.01 < g < i < h < 5.

6. The gallium nitride-based semiconductor laser according to claim 4, characterized in that, The dielectric constant of the first multi-vacancy electron-phonon modulation layer is m, the dielectric constant of the second multi-vacancy electron-phonon modulation layer is n, and the dielectric constant of the third multi-vacancy electron-phonon modulation layer is p, where: 2 < n < p < m < 20.

7. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The multiple vacancy electron-phonon modulation layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and diamond.

8. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The active layer is a periodic structure composed of a well layer and a barrier layer, with a period number of 3 ≥ m ≥ 1; The well layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 100 angstroms. The barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN, with a thickness of 10 angstroms to 200 angstroms.

9. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The lower confinement layer, lower waveguide layer, upper waveguide layer, and upper confinement layer are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, 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, and BN.

10. The gallium nitride-based semiconductor laser according to claim 1, characterized in that, The substrates include sapphire, silicon, CuW, Mo, TiW, Cu, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrates, sapphire / AlN composite substrates, and sapphire / SiN composite substrates. x Sapphire / SiO2 / SiN x The composite substrate, or any one of the following: magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2 composite substrate.

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