Epitaxial structure of compound semiconductor laser chip

Abstract

The invention discloses an epitaxial structure of a compound semiconductor laser chip, which sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer from bottom to top, the Bloch surface wave enhancement layer comprises a first Bloch surface wave enhancement layer, a second Bloch surface wave enhancement layer and a third Bloch surface wave enhancement layer. The Bloch surface wave enhancement layer forms polaritons in which excitons are strongly coupled with Bloch surface waves, the Bloch surface wave enhancement layer is induced to form polarization turning and spin polarizability through a local electric field, polarization reversal of the Bloch surface wave enhancement layer is regulated and controlled, negative polarization charges are shielded, the quantum confinement Stark effect is reduced, and the quantum confinement Stark effect is improved. And the nonlinear response and the electric lasing gain of the laser element are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor optoelectronic devices, and in particular to an epitaxial structure of a compound semiconductor laser chip. Background Art

[0002] Lasers are widely used in the fields of laser display, laser TV, laser projector, communication, medical treatment, weapons, guidance, ranging, spectral analysis, cutting, precision welding, high-density optical storage, etc. There are many types of lasers and various classification methods. The main types include solid-state, gas, liquid, semiconductor, and dye lasers. Compared with other types of lasers, all-solid-state semiconductor lasers have the advantages of small size, high efficiency, light weight, good stability, long life, simple and compact structure, and miniaturization.

[0003] There are significant differences between lasers and nitride semiconductor light-emitting diodes. 1) Laser is generated by stimulated emission of carriers, with a relatively small spectral full width at half maximum, very high brightness, and the output power of a single laser can be in the watt level, while nitride semiconductor light-emitting diodes are spontaneous emission, and the output power of a single light-emitting diode is in the milliwatt level. 2) The operating current density of lasers reaches KA / cm 2 which is more than two orders of magnitude higher than that of nitride light-emitting diodes, resulting in stronger electron leakage, more serious Auger recombination, stronger polarization effect, and more serious electron-hole mismatch, leading to a more serious efficiency droop effect. 3) Light-emitting diodes are spontaneous transition radiation, and without external action, they are incoherent light that transitions from a high energy level to a low energy level, while lasers are stimulated transition radiation, and the energy of the induced photon should be equal to the energy difference between the electron transitions, generating completely identical coherent light of the photon and the induced photon. 4) The principles are different: light-emitting diodes generate radiative recombination luminescence when electrons and holes transition to quantum wells or p-n junctions under the action of an external voltage, while lasers need to meet the lasing conditions to lase. It must satisfy the inverted distribution of carriers in the active region, and the stimulated emission light oscillates back and forth in the resonant cavity. The propagation in the gain medium amplifies the light, satisfies the threshold condition that the gain is greater than the loss, and finally outputs laser light.

[0004] The nitride semiconductor laser has the following problems: 1) The large lattice mismatch and strain in the active layer induce a strong piezopolarization effect, generating a strong QCSE (Quantum Confined Stark Effect), which limits the improvement of the electrical lasing gain of the laser; 2) The Mg acceptor in the p-type semiconductor has a large activation energy and low ionization efficiency. The hole concentration is much lower than the electron concentration, and the hole mobility is much smaller than the electron mobility. Moreover, problems such as the quantum well polarization electric field enhancing the hole injection barrier and holes spilling out of the active layer result in uneven hole injection and low efficiency, leading to a serious asymmetry and mismatch between electrons and holes in the quantum well, electron leakage, carrier delocalization, and more difficult hole transport in the quantum well. The carrier injection is uneven, the gain is uneven. At the same time, the gain spectrum of the laser broadens, and the peak gain decreases, resulting in an increase in the threshold current of the laser and a decrease in the slope efficiency. 3) The valence band offset of the laser increases, making hole transport in the quantum well more difficult, with uneven carrier injection and uneven gain. Summary of the Invention

[0005] The present invention proposes an epitaxial structure of a compound semiconductor laser chip. The Bloch surface wave enhancement layer forms polaritons with strong coupling between excitons and Bloch surface waves. By the local electric field, the Bloch surface wave enhancement layer forms polarization rotation and spin polarization rate, regulates the polarization reversal of the Bloch surface wave enhancement layer, shields the negative polarization charge, reduces the Quantum Confined Stark Effect, and improves the nonlinear response and electrical lasing gain of the laser element.

[0006] An epitaxial structure of a compound semiconductor laser chip provided by the present invention sequentially includes a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer from bottom to top. A Bloch surface wave enhancement layer is disposed above the upper confinement layer. The Bloch surface wave enhancement layer includes a first Bloch surface wave enhancement layer, a second Bloch surface wave enhancement layer, and a third Bloch surface wave enhancement layer.

[0007] Preferably, the longitudinal sound velocity distribution of the first Bloch surface wave enhancement layer has a third quadrant curve distribution of the function y = A + B*x + 1 / 2x; the longitudinal sound velocity distribution of the second Bloch surface wave enhancement layer has a linear function curve distribution; the longitudinal sound velocity distribution of the third Bloch surface wave enhancement layer has a curve distribution of the function y = C + D*lnx / e x The longitudinal sound velocity of the first Bloch surface wave enhancement layer is d, the longitudinal sound velocity of the second Bloch surface wave enhancement layer is e, and the longitudinal sound velocity of the third Bloch surface wave enhancement layer is f, where: 5E4 ≤ f ≤ e ≤ d ≤ 5E6 (cm / K).

[0008] Preferably, the valence band effective density of states distribution of the first Bloch surface wave enhancement layer has a curve distribution of the function y = E + F*x + 1 / 2x in the first quadrant; the valence band effective density of states distribution of the second Bloch surface wave enhancement layer has a linear function curve distribution; the valence band effective density of states distribution of the third Bloch surface wave enhancement layer has a curve distribution of the function y = G + H*x 2 / e x Curve distribution; the valence band effective density of states of the first Bloch surface wave enhancement layer is g, the valence band effective density of states of the second Bloch surface wave enhancement layer is h, and the valence band effective density of states of the third Bloch surface wave enhancement layer is i, where: 5E18 ≤ g ≤ h ≤ i ≤ 5E21.

[0009] Preferably, the density distribution of the first Bloch surface wave enhancement layer has a curve distribution of the function y = I + J*x 2 +K*e x Curve distribution; the density distribution of the second Bloch surface wave enhancement layer has a linear function curve distribution; the density distribution of the third Bloch surface wave enhancement layer has a curve distribution of the function y = L + M*sinx / x 2 Curve distribution in the first quadrant; the density of the first Bloch surface wave enhancement layer is j, the density of the second Bloch surface wave enhancement layer is k, and the density of the third Bloch surface wave enhancement layer is l, where: 2 ≤ j ≤ k ≤ l ≤ 30 (g / cm 3 ).

[0010] Preferably, the hole mobility distribution of the first Bloch surface wave enhancement layer has a curve distribution of the function y = N + P*lnx - Q*e x Curve distribution; the hole mobility distribution of the second Bloch surface wave enhancement layer has a linear function curve distribution; the hole mobility distribution of the third Bloch surface wave enhancement layer has a curve distribution of the function y = R + S*lnx / x; the hole mobility of the first Bloch surface wave enhancement layer is m, the hole mobility of the second Bloch surface wave enhancement layer is n, and the hole mobility of the third Bloch surface wave enhancement layer is p, where: 5 ≤ p ≤ n ≤ m ≤ 8000 (cm 2 / v / s).

[0011] Preferably, the Bloch surface wave enhancement 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, diamond, BiFeO3@Fe2Si, LaNiO3@BiFeO3, Fe3O4@Mn3O4, Mn3O4@LaNiO3, FeSe@BiFeO3.

[0012] Preferably, the active layer is a periodic structure composed of well layers and barrier layers, where the number of periods m satisfies 3≥m≥1. The well layer is any one or any combination of InGaN, InN, AlInN, GaN, with a thickness of 10 - 80 angstroms, and the barrier layer is any one or any combination of GaN, AlGaN, AlInGaN, AlN, AlInN, with a thickness of 1**********20 angstroms.

[0013] 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, BN, diamond.

[0014] Preferably, the substrate includes any one of sapphire, silicon, Ge, SiC, AlN, Cu, Mo, TiW, W, CuW, GaN, GaAs, InP, InAs, GaSb, diamond, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x 、sapphire / SiO2 / SiN x composite substrate, magnesium aluminate spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0015] It should be noted that in the translation of the thickness value in item , "1**********20 angstroms" in the original text seems to be an incorrect expression. It is recommended to check and correct it to a proper thickness range value for accurate translation. Here, it is translated as it is for the purpose of following the translation rules.Compared with the prior art, the epitaxial structure of a compound semiconductor laser chip provided by an embodiment of the present invention has the following beneficial effects: The Bloch surface wave enhancement layer forms polaritons with strong coupling between excitons and Bloch surface waves. By means of the local electric field, the Bloch surface wave enhancement layer is induced to form polarization rotation and spin polarization rate, regulate the polarization inversion of the Bloch surface wave enhancement layer, shield the negative polarization charge, reduce the quantum confinement Stark effect, enhance the nonlinear response and electro-luminescence gain of the laser element. At the same time, enhance the long-range energy transport of the Bloch surface wave enhancement layer, enhance the electron conductivity and polaritons, effectively separate and transport the charges of the polarization-induced built-in electric field, increase the propagation length of exciton polaritons, regulate the charge transport and the uniformity and matching of electron and hole injection in the active layer, improve the uniformity of the optical field distribution and the gain uniformity. At the same time, regulate the polarization vector of the Bloch surface wave enhancement layer, control the spin-orbit splitting and valley spin splitting, induce the reduction of the hole barrier height, improve the hole injection efficiency, reduce the electron overflow, enhance the strong coupling effect of the second harmonic, thereby reducing the optical field loss, improving the radiative recombination efficiency of the active layer of the laser element, reducing the excitation threshold of the laser element, and improving the optical power and slope efficiency of the laser element. Brief Description of the Drawings

[0016] Figure 1 FIG. is a schematic structural diagram of an epitaxial structure of a compound semiconductor laser chip provided by the present invention.

[0017] Figure 2 FIG. is a secondary ion mass spectrometry (SIMS) diagram of an epitaxial structure of a compound semiconductor laser chip provided by the present invention.

[0018] In the figure: 100: substrate; 101: lower confinement layer; 102: lower waveguide layer; 103: active layer; 104: upper waveguide layer; 105: upper confinement layer; 106: Bloch surface wave enhancement layer; 106a: first Bloch surface wave enhancement layer; 106b: second Bloch surface wave enhancement layer; 106c: third Bloch surface wave enhancement layer. Detailed Embodiments

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0020] To solve the above problems, the following specific embodiments will be used to introduce and explain in detail an epitaxial structure of a compound semiconductor laser chip provided by an embodiment of the present application.

[0021] Refer toFigure 1-2 , an epitaxial structure of a compound semiconductor laser chip provided by the present invention sequentially includes 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 from bottom to top. A Bloch surface wave enhancement layer 106 is disposed above the upper confinement layer 105. The Bloch surface wave enhancement layer 106 includes a first Bloch surface wave enhancement layer 106a, a second Bloch surface wave enhancement layer 106b, and a third Bloch surface wave enhancement layer 106c.

[0022] Among them, the Bloch surface wave enhancement 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, diamond, BiFeO3@Fe2Si, LaNiO3@BiFeO3, Fe3O4@Mn3O4, Mn3O4@LaNiO3, FeSe@BiFeO3.

[0023] The longitudinal sound velocity distribution of the first Bloch surface wave enhancement layer 106a has a third quadrant curve distribution of the function y = A + B * x + 1 / 2x; the longitudinal sound velocity distribution of the second Bloch surface wave enhancement layer 106b has a linear function curve distribution; the longitudinal sound velocity distribution of the third Bloch surface wave enhancement layer 106c has a function y = C + D * lnx / e x Curve distribution; the longitudinal sound velocity of the first Bloch surface wave enhancement layer 106a is d, the longitudinal sound velocity of the second Bloch surface wave enhancement layer 106b is e, and the longitudinal sound velocity of the third Bloch surface wave enhancement layer 106c is f, where: 5E4 ≤ f ≤ e ≤ d ≤ 5E6 (cm / K).

[0024] The valence band effective state density distribution of the first Bloch surface wave enhancement layer 106a has a first quadrant curve distribution of the function y = E + F * x + 1 / 2x; the valence band effective state density distribution of the second Bloch surface wave enhancement layer 106b has a linear function curve distribution; the valence band effective state density distribution of the third Bloch surface wave enhancement layer 106c has a function y = G + H * x 2 / e xCurve distribution; the valence band effective density of states of the first Bloch surface wave enhancement layer 106a is g, the valence band effective density of states of the second Bloch surface wave enhancement layer 106b is h, and the valence band effective density of states of the third Bloch surface wave enhancement layer 106c is i, where: 5E18 ≤ g ≤ h ≤ i ≤ 5E21.

[0025] The specific designed longitudinal sound velocity distribution and the specific designed valence band effective density of states distribution of the Bloch surface wave enhancement layer form polaritons with strong coupling between excitons and Bloch surface waves. By the local electric field, the Bloch surface wave enhancement layer is induced to form polarization rotation and spin polarization rate, regulate the polarization inversion of the Bloch surface wave enhancement layer, shield the negative polarization charge, reduce the quantum-confined Stark effect, enhance the long-range energy transport of the Bloch surface wave enhancement layer, enhance the electron conductance and polaritons, effectively separate and transport the charge of the polarization-induced built-in electric field, increase the propagation length of the exciton polaritons, regulate the charge transport and the uniformity and matching of the injection of electrons and holes in the active layer, improve the uniformity of the optical field distribution and the gain uniformity, enhance the nonlinear response and the electro-luminescence gain of the laser element, and increase the optical power and the slope efficiency of the laser element.

[0026] The density distribution of the first Bloch surface wave enhancement layer 106a has the function y = I + J * x 2 + K * e x Curve distribution; the density distribution of the second Bloch surface wave enhancement layer 106b has a linear function curve distribution; the density distribution of the third Bloch surface wave enhancement layer 106c has the function y = L + M * sinx / x 2 Curve distribution in the first quadrant; the density of the first Bloch surface wave enhancement layer 106a is j, the density of the second Bloch surface wave enhancement layer 106b is k, and the density of the third Bloch surface wave enhancement layer 106c is l, where: 2 ≤ j ≤ k ≤ l ≤ 30 (g / cm 3 ).

[0027] The hole mobility distribution of the first Bloch surface wave enhancement layer 106a has the function y = N + P * lnx - Q * e x Curve distribution; the hole mobility distribution of the second Bloch surface wave enhancement layer 106b has a linear function curve distribution; the hole mobility distribution of the third Bloch surface wave enhancement layer 106c has the function y = R + S * lnx / x curve distribution; the hole mobility of the first Bloch surface wave enhancement layer 106a is m, the hole mobility of the second Bloch surface wave enhancement layer 106b is n, and the hole mobility of the third Bloch surface wave enhancement layer 106c is p, where: 5 ≤ p ≤ n ≤ m ≤ 8000 (cm 2 / v / s).

[0028] The density distribution with a specific design and the hole mobility distribution with a specific design of the Bloch surface wave enhancement layer regulate the polarization vector of the Bloch surface wave enhancement layer, control the spin-orbit splitting and the valley spin splitting, induce a decrease in the hole barrier height, improve the hole injection efficiency, reduce the electron overflow, enhance the second-harmonic strong coupling effect, thereby reducing the optical field loss, improving the radiative recombination efficiency of the active layer of the laser element, reducing the excitation threshold of the laser element, and improving the optical power and slope efficiency of the laser element.

[0029] Specifically, as shown in the following table, the data of the traditional laser and the laser of the present invention are compared.

[0030]

[0031] In the present invention, the active layer 103 is a periodic structure composed of well layers and barrier layers, the number of periods is 3≥m≥1, the well layer is any one or any combination of InGaN, InN, AlInN, GaN, with a thickness of 10-80 angstroms, and the barrier layer is any one or any combination of GaN, AlGaN, AlInGaN, AlN, AlInN, with a thickness of 10-120 angstroms.

[0032] In the present invention, 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, BN, diamond.

[0033] In the present invention, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, Cu, Mo, TiW, W, CuW, GaN, GaAs, InP, InAs, GaSb, diamond, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x 、sapphire / SiO2 / SiN x composite substrate, magnesium aluminate spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate, any one of them.

[0034] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An epitaxial structure of a compound semiconductor laser chip, which sequentially includes 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) from bottom to top, and is characterized in that, Above the upper confinement layer (105), there is a Bloch surface wave enhancement layer (106).

2. The epitaxial structure of a compound semiconductor laser chip according to claim 1, wherein, The Bloch surface wave enhancement layer (106) includes a first Bloch surface wave enhancement layer (106a), a second Bloch surface wave enhancement layer (106b), and a third Bloch surface wave enhancement layer (106c).

3. The epitaxial structure of a compound semiconductor laser chip according to claim 2, characterized in that, The longitudinal sound velocity distribution of the first Bloch surface wave enhancement layer (106a) has a third quadrant curve distribution of the function y = A + B*x + 1 / 2x; the longitudinal sound velocity distribution of the second Bloch surface wave enhancement layer (106b) has a linear function curve distribution; the longitudinal sound velocity distribution of the third Bloch surface wave enhancement layer (106c) has the function y = C + D*lnx / e x Curve distribution; the longitudinal sound velocity of the first Bloch surface wave enhancement layer (106a) is d, the longitudinal sound velocity of the second Bloch surface wave enhancement layer (106b) is e, and the longitudinal sound velocity of the third Bloch surface wave enhancement layer (106c) is f, where: 5E4 ≤ f ≤ e ≤ d ≤ 5E6 (cm / K).

4. The epitaxial structure of a compound semiconductor laser chip according to claim 2, characterized in that, The valence band effective density of states distribution of the first Bloch surface wave enhancement layer (106a) has a curve distribution of the function y = E + F * x + 1 / 2x in the first quadrant; the valence band effective density of states distribution of the second Bloch surface wave enhancement layer (106b) has a linear function curve distribution; the valence band effective density of states distribution of the third Bloch surface wave enhancement layer (106c) has a curve distribution of the function y = G + H * x 2 / e x ; the valence band effective density of states of the first Bloch surface wave enhancement layer (106a) is g, the valence band effective density of states of the second Bloch surface wave enhancement layer (106b) is h, and the valence band effective density of states of the third Bloch surface wave enhancement layer (106c) is i, where: 5E18 ≤ g ≤ h ≤ i ≤ 5E21.

5. The epitaxial structure of a compound semiconductor laser chip according to claim 2, characterized in that, The density distribution of the first Bloch surface wave enhancement layer (106a) has a functional curve of y = I + J * x 2 + K * e x curve distribution; the density distribution of the second Bloch surface wave enhancement layer (106b) has a linear functional curve distribution; the density distribution of the third Bloch surface wave enhancement layer (106c) has a functional curve of y = L + M * sinx / x 2 in the first quadrant curve distribution; the density of the first Bloch surface wave enhancement layer (106a) is j, the density of the second Bloch surface wave enhancement layer (106b) is k, and the density of the third Bloch surface wave enhancement layer (106c) is l, where: 2 ≤ j ≤ k ≤ l ≤ 30 (g / cm 3 ).

6. The epitaxial structure of a compound semiconductor laser chip according to claim 2, characterized in that, The hole mobility distribution of the first Bloch surface wave enhancement layer (106a) has a function y = N + P*lnx - Q*e x curve distribution; the hole mobility distribution of the second Bloch surface wave enhancement layer (106b) has a linear function curve distribution; the hole mobility distribution of the third Bloch surface wave enhancement layer (106c) has a function y = R + S*lnx / x curve distribution; the hole mobility of the first Bloch surface wave enhancement layer (106a) is m, the hole mobility of the second Bloch surface wave enhancement layer (106b) is n, and the hole mobility of the third Bloch surface wave enhancement layer (106c) is p, where: 5 ≤ p ≤ n ≤ m ≤ 8000 (cm 2 / v / s).

7. The epitaxial structure of a compound semiconductor laser chip according to claim 1, characterized in that, The Bloch surface wave enhancement 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, diamond, BiFeO3@Fe2Si, LaNiO3@BiFeO3, Fe3O4@Mn3O4, Mn3O4@LaNiO3, FeSe@BiFeO3.

8. The epitaxial structure of a compound semiconductor laser chip according to claim 1, characterized in that, The active layer (103) is a periodic structure composed of well layers and barrier layers, with the number of periods 3≥m≥1. The well layer is any one or any combination of InGaN, InN, AlInN, GaN, with a thickness of 10 - 80 angstroms, and the barrier layer is any one or any combination of GaN, AlGaN, AlInGaN, AlN, AlInN, with a thickness of 10 - 120 angstroms.

9. The epitaxial structure of a compound semiconductor laser chip according to claim 1, characterized in that, 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, BN, diamond.

10. The epitaxial structure of a compound semiconductor laser chip according to claim 1, characterized in that, The substrate (100) includes any one of sapphire, silicon, Ge, SiC, AlN, Cu, Mo, TiW, W, CuW, GaN, GaAs, InP, InAs, GaSb, diamond, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , sapphire / SiO2 / SiN x composite substrate, magnesium aluminate spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2, and LiGaO2 composite substrate.

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