Epitaxial structure of gallium nitride-based semiconductor laser

Abstract

The epitaxial structure comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer which are sequentially arranged from bottom to top, and a first Dirac quantum tunnel layer is arranged between the lower waveguide layer and the lower limiting layer. The first Dirac quantum tunnel layer has a thermal expansion coefficient distribution characteristic, a Si / Mg element proportion distribution characteristic and an In / Si element proportion distribution characteristic. According to the invention, transition and radiation recombination of holes of the active layer through the Dirac quantum tunnel layer can be enhanced, the quantum confinement effect of the active layer is improved, and hole leakage and hole overflow effects of the first Dirac quantum tunnel layer and the active layer are reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor optoelectronic devices, and in particular to an epitaxial structure of a gallium nitride-based semiconductor laser. Background Art

[0002] Lasers are widely used in laser display, laser TV, laser projector, communication, medical treatment, weapons, guidance, ranging, spectral analysis, cutting, precision welding, high-density optical storage and other fields. There are many types of lasers, and the classification methods are also diverse, mainly including solid, gas, liquid, semiconductor and dye types of 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 big differences between lasers and nitride semiconductor light-emitting diodes:

[0004] 1) Laser is generated by stimulated radiation of carriers, the spectrum half-width is small, the brightness is very high, and the output power of a single laser can be in the W level, while nitride semiconductor light-emitting diodes are spontaneously radiated, and the output power of a single light-emitting diode is in the mW level;

[0005] 2) The current density of the laser reaches KA / cm2, which is more than 2 orders of magnitude higher than that of nitride light-emitting diodes, resulting in stronger electron leakage, more serious Auger recombination, stronger polarization effect, more serious electron-hole mismatch, and more serious efficiency attenuation Droop effect;

[0006] 3) The spontaneous transition radiation of the light-emitting diode is incoherent light that transitions from a high energy level to a low energy level without any external influence, while the laser is stimulated transition radiation, and the energy of the induced photon should be equal to the difference in the energy level of the electron transition, producing the same coherent light as the photon and the induced photon;

[0007] 4) Different principles: When an external voltage is applied to a light-emitting diode, electron holes jump to a quantum well or a pn junction to generate radiative recombination light, while a laser can only emit when the lasing conditions are met. The carrier distribution in the active region must be reversed, and the stimulated radiation light oscillates back and forth in the resonant cavity. The propagation in the gain medium amplifies the light, and the threshold condition is met so that the gain is greater than the loss, and finally the laser is output.

[0008] Nitride semiconductor lasers have the following problems: the activation energy of the Mg acceptor of the p-type semiconductor is large, the ionization efficiency is low, the hole concentration is much lower than the electron concentration, the hole mobility is much lower than the electron mobility, and the quantum well polarization electric field increases the hole injection barrier, the holes overflow the active layer, and other problems. The hole injection is uneven and the efficiency is low, resulting in serious asymmetric mismatch between electrons and holes in the quantum well, electron leakage and carrier delocalization, more difficult hole transport in the quantum well, uneven carrier injection, uneven gain, and at the same time, the laser gain spectrum becomes wider and the peak gain decreases, resulting in an increase in the laser threshold current and a decrease in slope efficiency. The laser valence band step difference increases, holes are more difficult to transport in the quantum well, carrier injection is uneven, and gain is uneven. Summary of the invention

[0009] In order to solve one of the above technical problems, the present invention provides an epitaxial structure of a gallium nitride-based semiconductor laser.

[0010] An embodiment of the present invention provides an epitaxial structure of a gallium nitride-based semiconductor laser, comprising a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper confinement layer arranged in sequence from bottom to top, wherein a first Dirac quantum tunnel layer is arranged between the lower waveguide layer and the lower confinement layer, and the first Dirac quantum tunnel layer has a thermal expansion coefficient distribution characteristic, a Si / Mg element ratio distribution characteristic and an In / Si element ratio distribution characteristic;

[0011] The thermal expansion coefficient of the first Dirac quantum tunnel layer has a function y 1 =A+B*x 1 e x1 Curve distribution;

[0012] The Si / Mg element ratio of the first Dirac quantum tunnel layer has a function y 2 =C+D*lnx 1 / x 1 Curve distribution;

[0013] The In / Si element ratio of the first Dirac quantum tunnel layer has a function y 3 =E+F*cosx 1 / x 1 The second and third quadrant curve distribution;

[0014] Among them, x 1 is the depth from the first Dirac quantum tunnel layer to the lower waveguide layer.

[0015] Preferably, the first Dirac quantum tunnel layer also has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics;

[0016] The elastic coefficient of the first Dirac quantum tunneling layer has a function y4 =G+H*e x1 / x 1 2 The second quadrant curve distribution;

[0017] The refractive index coefficient of the first Dirac quantum tunnel layer has a function y 5 =I+J*x 1 2 e x1 Curve distribution;

[0018] The spontaneous polarization coefficient of the first Dirac quantum tunneling layer has a function y 6 =K+L*x 1 e x1 Curved distribution.

[0019] Preferably, the first Dirac quantum tunnel layer is InGaN, GaN, AlGaN, AlInN, AlInGaN, AlN, InN, BN, Ga 2 O 3 Any one or any combination of the foregoing, wherein the thickness of the first Dirac quantum tunnel layer is 5 angstroms to 5000 angstroms.

[0020] Preferably, a second Dirac quantum tunnel layer is provided between the upper waveguide layer and the upper confinement layer, and the second Dirac quantum tunnel layer has a thermal expansion coefficient distribution characteristic, a Mg / Si element ratio distribution characteristic, and an In / Si element ratio distribution characteristic;

[0021] The thermal expansion coefficient of the second Dirac quantum tunnel layer has a function y 7 =M+N*x 2 2 sinx 2 The first and fourth quadrants curve distribution;

[0022] The Mg / Si element ratio of the second Dirac quantum tunnel layer has a function y 8 =O+P*e x2 sinx 2 Curve distribution;

[0023] The In / Si element ratio of the second Dirac quantum tunnel layer has a function y 9 =ax 2 3 +bx 2 2 +cx 2 +d(a>0,△=4(b 2 -3ac)≤0) curve distribution;

[0024] Among them, x 2is the depth from the second Dirac quantum tunnel layer to the upper confinement layer.

[0025] Preferably, the second Dirac quantum tunnel layer also has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics;

[0026] The elastic coefficient of the second Dirac quantum tunneling layer has the function y 10 =Q+R*e x2 -T*sinx 2 Curve distribution;

[0027] The refractive index coefficient of the second Dirac quantum tunnel layer has a function y 11 =S+U*e x2 +V*sinx 2 Curve distribution;

[0028] The spontaneous polarization coefficient of the second Dirac quantum tunneling layer has the function y 12 =W+e x2 +Z*cosx 2 Curved distribution.

[0029] Preferably, the second Dirac quantum tunnel layer is InGaN, GaN, AlGaN, AlInN, AlInGaN, AlN, InN, BN, Ga 2 O 3 Any one or any combination of the foregoing, wherein the thickness of the first Dirac quantum tunnel layer is 5 angstroms to 5000 angstroms.

[0030] Preferably, the lower limiting layer and the upper limiting layer are any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, and AlInN, and have a thickness of 10 angstroms to 80,000 angstroms.

[0031] Preferably, the lower waveguide layer and the upper waveguide layer are any one or any combination of GaN, InGaN, AlInGaN, AlInN, and InN, and have a thickness of 5 angstroms to 20,000 angstroms.

[0032] Preferably, the light-emitting wavelength of the active layer is 200nm to 420nm, the active layer is a periodic structure composed of a well layer and a barrier layer, the number of periods is 3≥m≥1, the well layer is any one or any combination of InGaN, InN, AlInN, GaN, AlGaN, AlInGaN, AlN, and AlN, and the thickness is 10 angstroms to 100 angstroms, and the barrier layer is any one or any combination of GaN, AlGaN, AlInGaN, AlN, and AlInN, and the thickness is 10 angstroms to 200 angstroms.

[0033] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO 2 Composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO 2 / SiN x Composite substrate, magnesium aluminum spinel MgAl 2 O 4 、MgO、ZnO、ZrB 2 、LiAlO 2 and LiGaO 2 Any type of composite substrate.

[0034] The beneficial effects of the present invention are as follows: the present invention arranges a first Dirac quantum tunnel layer between the lower waveguide layer and the lower confinement layer of the epitaxial structure of the gallium nitride-based semiconductor laser, and designs the thermal expansion coefficient distribution characteristics, Si / Mg element ratio distribution characteristics and In / Si element ratio distribution characteristics of the first Dirac quantum tunnel layer, which can enhance the transition and radiation recombination of the holes in the active layer through the Dirac quantum tunnel layer, enhance the quantum confinement effect of the active layer, and reduce the hole leakage and hole overflow effects of the first Dirac quantum tunnel layer and the active layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0036] Figure 1 This is a schematic structural diagram of the epitaxial structure of the gallium nitride-based semiconductor laser according to Embodiment 1 of the present invention;

[0037] Figure 2 A schematic diagram of the epitaxial structure of the gallium nitride-based semiconductor laser according to Embodiment 2 of the present invention

[0038] Figure 3 This is a SIMS secondary ion mass spectrum of the epitaxial structure of the gallium nitride-based semiconductor laser described in Example 2 of the present invention.

[0039] Reference numerals:

[0040] 100, substrate, 101, lower confinement layer, 102, lower waveguide layer, 103, active layer, 104, upper waveguide layer, 105, upper confinement layer;

[0041] 106a, a first Dirac quantum tunneling layer, 106b, a second Dirac quantum tunneling layer. DETAILED DESCRIPTION

[0042] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0043] Example 1

[0044] like Figure 1 As shown, this embodiment provides an epitaxial structure of 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 in sequence from bottom to top. A first Dirac quantum tunnel layer 106a is also arranged in the epitaxial structure of the gallium nitride-based semiconductor laser.

[0045] Specifically, in this embodiment, the epitaxial structure of the gallium nitride-based semiconductor laser is provided with 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 in order from bottom to top. The first Dirac quantum tunnel layer 106a is provided between the lower waveguide layer 102 and the lower confinement layer 101.

[0046] In this embodiment, the first Dirac quantum tunnel layer 106a has a thermal expansion coefficient distribution characteristic, a Si / Mg element ratio distribution characteristic, and an In / Si element ratio distribution characteristic, which are specifically manifested as follows:

[0047] The thermal expansion coefficient of the first Dirac quantum tunnel layer 106a has a function y 1 =A+B*x 1 e x1 Curve distribution;

[0048] The Si / Mg element ratio of the first Dirac quantum tunnel layer 106a has a function y 2 =C+D*lnx 1 / x 1 Curve distribution;

[0049] The In / Si element ratio of the first Dirac quantum tunnel layer 106a has a function y 3 =E+F*cosx 1 / x 1 The second and third quadrant curve distribution;

[0050] Among them, x 1 is the depth from the first Dirac quantum tunnel layer 106 a to the lower waveguide layer 102 .

[0051] In this embodiment, by arranging a first Dirac quantum tunnel layer 106a between the lower waveguide layer 102 and the lower confinement layer 101, and designing the thermal expansion coefficient distribution characteristics, Si / Mg element ratio distribution characteristics, and In / Si element ratio distribution characteristics of the first Dirac quantum tunnel layer 106a, the holes in the active layer 103 can be enhanced to perform transition and radiation recombination through the Dirac quantum tunnel layer, thereby improving the quantum confinement effect of the active layer 103 and reducing the hole leakage and hole overflow effects of the first Dirac quantum tunnel layer 106a and the active layer 103.

[0052] In some optional embodiments, the first Dirac quantum tunnel layer 106a further has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics, which are specifically manifested as follows:

[0053] The elastic coefficient of the first Dirac quantum tunneling layer 106a has a function y 4 =G+H*e x1 / x 1 2 The second quadrant curve distribution;

[0054] The refractive index coefficient of the first Dirac quantum tunnel layer 106a has a function y 5 =I+J*x 1 2 e x1 Curve distribution;

[0055] The spontaneous polarization coefficient of the first Dirac quantum tunneling layer 106a has the function y 6 =K+L*x 1 e x1 Curved distribution.

[0056] By designing the elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics of the first Dirac quantum tunnel layer 106a, the matching degree of the electron-hole concentration in the active layer 103 can be enhanced, the non-radiative recombination probability caused by the overflow of holes to the lower confinement layer 101 can be reduced, the threshold current density can be reduced and the slope efficiency can be improved.

[0057] In some optional embodiments, the first Dirac quantum tunnel layer 106a is InGaN, GaN, AlGaN, AlInN, AlInGaN, AlN, InN, BN, Ga 2 O 3 The thickness of the first Dirac quantum tunnel layer 106a is 5 angstroms to 5000 angstroms.

[0058] In some optional embodiments, the lower confinement layer 101 and the upper confinement layer 105 are any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, and AlInN, and have a thickness of 10 angstroms to 80,000 angstroms.

[0059] In some optional embodiments, the lower waveguide layer 102 and the upper waveguide layer 104 are any one or any combination of GaN, InGaN, AlInGaN, AlInN, and InN, and have a thickness of 5 angstroms to 20,000 angstroms.

[0060] In some optional embodiments, the light emission wavelength of the active layer 103 is 200 nm to 420 nm.

[0061] The active layer 103 is a periodic structure composed of a well layer and a barrier layer, and the number of periods is 3≥m≥1.

[0062] Specifically, the well layer of the active layer 103 is any one or any combination of InGaN, InN, AlInN, GaN, AlGaN, AlInGaN, and AlN, and has a thickness of 10 angstroms to 100 angstroms.

[0063] The barrier layer of the active layer 103 is any one or any combination of GaN, AlGaN, AlInGaN, AlN, and AlInN, and has a thickness of 10 angstroms to 200 angstroms.

[0064] In some optional embodiments, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO 2 Composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO 2 / SiN x Composite substrate, magnesium aluminum spinel MgAl 2 O 4 、MgO、ZnO、ZrB 2 、LiAlO 2 and LiGaO 2 Any type of composite substrate.

[0065] Example 2

[0066] like Figure 2 and Figure 3As shown, based on Example 1, in the epitaxial structure of a gallium nitride-based semiconductor laser proposed in this embodiment, a second Dirac quantum tunnel layer 106b is further provided between the upper waveguide layer 104 and the upper confinement layer 105. The second Dirac quantum tunnel layer 106b has a thermal expansion coefficient distribution characteristic, a Mg / Si element ratio distribution characteristic, and an In / Si element ratio distribution characteristic, which are specifically manifested as follows:

[0067] The thermal expansion coefficient of the second Dirac quantum tunnel layer 106b has a function y 7 =M+N*x 2 2 sinx 2 The first and fourth quadrants curve distribution;

[0068] The Mg / Si element ratio of the second Dirac quantum tunnel layer 106b has a function y 8 =O+P*e x2 sinx 2 Curve distribution;

[0069] The In / Si element ratio of the second Dirac quantum tunnel layer 106b has a function y 9 =ax 2 3 +bx 2 2 +cx 2 +d(a>0,△=4(b 2 -3ac)≤0) curve distribution;

[0070] Among them, x 2 is the depth of the second Dirac quantum tunnel layer 106 b toward the upper confinement layer 105 .

[0071] In addition, the second Dirac quantum tunnel layer 106b also has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics, which are specifically manifested as follows:

[0072] The elastic coefficient of the second Dirac quantum tunneling layer 106b has a function y 10 =Q+R*e x2 -T*sinx 2 Curve distribution;

[0073] The refractive index coefficient of the second Dirac quantum tunnel layer 106b has a function y 11 =S+U*e x2 +V*sinx 2 Curve distribution;

[0074] The spontaneous polarization coefficient of the second Dirac quantum tunneling layer 106b has the function y 12 =W+ex2 +Z*cosx 2 Curved distribution.

[0075] In this embodiment, by arranging a second Dirac quantum tunnel layer 106 b between the upper waveguide layer 104 and the upper confinement layer 105, and designing the thermal expansion coefficient distribution characteristics, Si / Mg element ratio distribution characteristics, In / Si element ratio distribution characteristics, elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics of the second Dirac quantum tunnel layer 106 b, it is possible to enhance the transition and radiative recombination of electrons in the active layer 103 through the Dirac quantum tunnel layer, improve the quantum confinement effect of the active layer 103, reduce the electron leakage and electron overflow effect of the second Dirac quantum tunnel layer 106 b and the active layer 103, enhance the matching degree of the electron-hole concentration in the active layer 103, reduce the non-radiative recombination probability caused by the electron overflow to the upper confinement layer 105, reduce the threshold current density and improve the slope efficiency.

[0076] The following table is a parameter comparison of the epitaxial structure of a conventional semiconductor laser element and the gallium nitride-based semiconductor laser proposed in this embodiment, including slope efficiency and threshold current density to show the difference between the epitaxial structure of the conventional semiconductor laser element and the gallium nitride-based semiconductor laser proposed in this embodiment:

[0077]

[0078]

[0079] It can be seen that the epitaxial structure of the gallium nitride-based semiconductor laser proposed in this embodiment improves the slope efficiency and reduces the threshold current density compared with the traditional semiconductor laser elements, and has obvious advantages over the traditional semiconductor laser elements.

[0080] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. An epitaxial structure of a gallium nitride-based semiconductor laser, comprising a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper confinement layer arranged in sequence from bottom to top, characterized in that: A first Dirac quantum tunnel layer is provided between the lower waveguide layer and the lower confinement layer, wherein the first Dirac quantum tunnel layer has a thermal expansion coefficient distribution characteristic, a Si / Mg element ratio distribution characteristic, and an In / Si element ratio distribution characteristic; The thermal expansion coefficient of the first Dirac quantum tunnel layer has the function y1=A+B*x1e x1 Curve distribution; The Si / Mg element ratio of the first Dirac quantum tunnel layer has a function y2=C+D*lnx1 / x1 curve distribution; The In / Si element ratio of the first Dirac quantum tunnel layer has a second three-quadrant curve distribution of the function y3=E+F*cosx1 / x1; Wherein, x1 is the depth from the first Dirac quantum tunnel layer to the lower waveguide layer.

2. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: The first Dirac quantum tunnel layer also has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics; The elastic coefficient of the first Dirac quantum tunnel layer has the function y4=G+H*e x1 / x1 2 The second quadrant curve distribution; The refractive index coefficient of the first Dirac quantum tunnel layer has the function y5=I+J*x1 2 e x1 Curve distribution; The spontaneous polarization coefficient of the first Dirac quantum tunnel layer has the function y6=K+L*x1e x1 Curved distribution.

3. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: The first Dirac quantum tunnel layer is any one or any combination of InGaN, GaN, AlGaN, AlInN, AlInGaN, AlN, InN, BN, and Ga2O3, and the thickness of the first Dirac quantum tunnel layer is 5 angstroms to 5000 angstroms.

4. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: A second Dirac quantum tunnel layer is provided between the upper waveguide layer and the upper confinement layer, wherein the second Dirac quantum tunnel layer has a thermal expansion coefficient distribution characteristic, a Mg / Si element ratio distribution characteristic, and an In / Si element ratio distribution characteristic; The thermal expansion coefficient of the second Dirac quantum tunnel layer has the function y7=M+N*x2 2 sinx2 first and fourth quadrant curve distribution; The Mg / Si element ratio of the second Dirac quantum tunnel layer has the function y8=O+P*e x2 sinx2 curve distribution; The In / Si element ratio of the second Dirac quantum tunnel layer has the function y9=ax2 3 +bx2 2 +cx2+d(a>0,△=4(b 2 -3ac)≤0) curve distribution; Wherein, x2 is the depth from the second Dirac quantum tunnel layer to the upper confinement layer.

5. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 4, characterized in that: The second Dirac quantum tunnel layer also has elastic coefficient distribution characteristics, refractive index coefficient distribution characteristics and spontaneous polarization coefficient distribution characteristics; The elastic coefficient of the second Dirac quantum tunneling layer has the function y 10 =Q+R*e x2 -T*sinx2 curve distribution; The refractive index coefficient of the second Dirac quantum tunnel layer has a function y 11 =S+U*e x2 +V*sinx2 curve distribution; The spontaneous polarization coefficient of the second Dirac quantum tunneling layer has the function y 12 =W+e x2 +Z*cosx2 curve distribution.

6. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 4, characterized in that: The second Dirac quantum tunnel layer is any one or any combination of InGaN, GaN, AlGaN, AlInN, AlInGaN, AlN, InN, BN, and Ga2O3, and the thickness of the first Dirac quantum tunnel layer is 5 angstroms to 5000 angstroms.

7. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: The lower limiting layer and the upper limiting layer are any one or any combination of GaN, AlGaN, InGaN, AlInGaN, AlN, InN, and AlInN, and have a thickness of 10 angstroms to 80,000 angstroms.

8. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: The lower waveguide layer and the upper waveguide layer are any one or any combination of GaN, InGaN, AlInGaN, AlInN, and InN, and have a thickness of 5 angstroms to 20,000 angstroms.

9. The epitaxial structure of the gallium nitride-based semiconductor laser according to claim 1, characterized in that: The light emitting wavelength of the active layer is 200nm to 420nm. 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. The well layer is any one or any combination of InGaN, InN, AlInN, GaN, AlGaN, AlInGaN, and AlN, and has a thickness of 10 to 100 angstroms. The barrier layer is any one or any combination of GaN, AlGaN, AlInGaN, AlN, and AlInN, and has a thickness of 10 to 200 angstroms.

10. The epitaxial structure of a gallium nitride-based semiconductor laser according to claim 1, characterized in that: The substrate includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

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