A gallium nitride-based semiconductor laser having a divergence angle modulation layer

Abstract

The application provides a gallium nitride-based semiconductor laser with a divergence angle modulation layer, which comprises, from bottom to top, a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, an upper limiting layer and a contact layer, wherein the lower limiting layer comprises, from bottom to top, a first lower limiting layer, a second lower limiting layer and a third lower limiting layer, a first divergence angle modulation layer is arranged between the substrate and the first lower limiting layer, and a second divergence angle modulation layer is arranged between the second lower limiting layer and the third lower limiting layer. The normalized Al atomic concentration curves of the SIMS tests of the first divergence angle modulation layer and the second divergence angle modulation layer both satisfy Lorentz function distribution, so that a carrier transverse expansion region is formed in the first divergence angle modulation layer and the second divergence angle modulation layer, the transverse expansion and mobility of carriers are enhanced, the active layer recombination width in the horizontal divergence angle direction of the laser is increased, and the horizontal divergence angle is enlarged.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor optoelectronic devices, and in particular to a gallium nitride-based semiconductor laser with a divergence angle modulation layer. BACKGROUND

[0002] Lasers are widely used in laser display, laser television, laser projector, communication, medical treatment, weapon, guidance, distance measurement, spectrum analysis, cutting, precision welding, high-density optical storage and other fields. There are many types of lasers, and the classification methods are various. The main types of lasers 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 service life, simple and compact structure, and small size.

[0003] There are great differences between lasers and nitride semiconductor light-emitting diodes:

[0004] 1) Laser is generated by stimulated radiation of carriers, with small spectral half-width and high brightness. The output power of a single laser can reach W level, while the output power of a single nitride semiconductor light-emitting diode is in the mW level.

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

[0006] 3) Light-emitting diode is spontaneously transitioned and radiated without external action, and incoherent light is transitioned from high energy level to low energy level. Laser is stimulated transition radiation, and the energy of the induced photon should be equal to the energy level difference of the electron transition. Homogeneous coherent light is generated by the induced photon.

[0007] 4) Different principles: Light-emitting diode is under the action of external voltage, and electron-hole transition occurs in the active layer or p-n junction to produce radiation recombination and light emission. Laser needs to meet the lasing conditions, and must meet the carrier inversion distribution in the active region. The stimulated radiation light oscillates back and forth in the resonant cavity, propagates in the gain medium to amplify the light, and finally outputs laser when the gain is greater than the loss and the threshold condition is met.

[0008] The nitride semiconductor laser has the following problems: The confinement effect of the lower confinement layer of the GaN-based laser is limited, which may cause substrate mode leakage. The horizontal divergence angle of the laser is too small, which may make the far-field spot shape of the laser deviate from the Gaussian distribution and become elongated, resulting in poor effect in display and indication fields. SUMMARY

[0009] To solve one of the above technical problems, the application provides a gallium nitride-based semiconductor laser with a divergence angle modulation layer.

[0010] The gallium nitride-based semiconductor laser with a divergence angle modulation layer comprises, from bottom to top, a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, an upper limiting layer and a contact layer, the lower limiting layer comprises, from bottom to top, a first lower limiting layer, a second lower limiting layer and a third lower limiting layer, a first divergence angle modulation layer is arranged between the substrate and the first lower limiting layer, and a second divergence angle modulation layer is arranged between the second lower limiting layer and the third lower limiting layer.

[0011] The normalized Al atomic concentration curve of the SIMS test of the first divergence angle modulation layer and the second divergence angle modulation layer both satisfy a Lorentz function distribution y=y0+(2A / π)×(w / (4×(x-x c ) 2 +w 2 )), wherein x is the thickness of the epitaxial layer of the SIMS test, the zero point is the surface of the epitaxial layer, y is the normalized Al atomic concentration of the SIMS test, y0 is the baseline offset, x c is the peak center position, w is the full width at half maximum, and A is the peak area.

[0012] Preferably, in the normalized Al atomic concentration curve function of the SIMS test of the first divergence angle modulation layer, -0.08≤y0≤-0.02, 2≤x c ≤6, 0.005≤w≤0.5, and 0.002≤A≤1.

[0013] Preferably, in the normalized Al atomic concentration curve function of the SIMS test of the second divergence angle modulation layer, -0.08≤y0≤-0.02, 1≤x c ≤5, 0.005≤w≤0.5, and 0.005≤A≤0.5.

[0014] Preferably, the baseline offset of the first divergence angle modulation layer is greater than or equal to the baseline offset of the second divergence angle modulation layer, the peak center position of the first divergence angle modulation layer is greater than or equal to the peak center position of the second divergence angle modulation layer, the full width at half maximum of the first divergence angle modulation layer is greater than or equal to the full width at half maximum of the second divergence angle modulation layer, and the peak area of the first divergence angle modulation layer is greater than or equal to the peak area of the second divergence angle modulation layer.

[0015] Preferably, the first divergence angle modulation layer is any combination of GaN, AlGaN, AlInGaN and AlN, and the thickness of the first divergence angle modulation layer is 5 angstroms to 800 angstroms.

[0016] Preferably, the second divergence angle modulation layer is any combination of GaN, AlGaN, AlInGaN, AlN, and InGaN, and the thickness of the second divergence angle modulation layer is from 5 angstroms to 500 angstroms.

[0017] Preferably, the first lower confining layer is any combination of GaN, AlGaN, and AlN, the second lower confining layer is any combination of InGaN, GaN, and AlN, and the third lower confining layer is any combination of GaN, AlGaN, and AlN.

[0018] Preferably, the substrate is a GaN single crystal substrate;

[0019] The lower waveguide layer is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN.

[0020] The active layer is an InGaN / GaN quantum well;

[0021] The upper waveguide layer is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN.

[0022] The electron blocking layer is any combination of AlGaN, GaN, InGaN, AlInGaN, or AlN.

[0023] The upper confinement layer is any one of AlGaN or AlGaN / GaN or AlN / AlGaN / GaN or AlN / AlInGaN / AlGaN / GaN or AlInGaN / AlGaN / GaN.

[0024] The contact layer is any combination of AlGaN, GaN, InGaN, and AlInGaN.

[0025] Preferably, the lower waveguide layer is a combination of GaN and InGaN, the upper waveguide layer is a combination of InGaN and InGaN, the upper confinement layer is a combination of AlGaN and AlGaN, the electron blocking layer is a combination of AlN and AlGaN, and the contact layer is GaN.

[0026] Preferably, the thickness of the lower waveguide layer is 300 Å to 8000 Å, the thickness of the upper waveguide layer is 300 Å to 8000 Å, the thickness of the upper confinement layer is 500 Å to 9000 Å, the thickness of the electron blocking layer is 5 Å to 800 Å, and the thickness of the contact layer is 5 Å to 2000 Å.

[0027] The beneficial effects of this invention are as follows: This invention designs the lower confinement layer in a gallium nitride-based semiconductor laser as a three-layer structure, and sets a first divergence angle modulation layer between the substrate and the first lower confinement layer, and a second divergence angle modulation layer between the second lower confinement layer and the third lower confinement layer. At the same time, the normalized Al atom concentration curves of the SIMS test of the first and second divergence angle modulation layers both satisfy the Lorentz function distribution, thereby forming a carrier lateral expansion region between the first and second divergence angle modulation layers, enhancing the lateral expansion and mobility of carriers, increasing the active layer recombination width in the horizontal divergence direction of the laser, and thus expanding the horizontal divergence angle. 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 a gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention;

[0030] Figure 2 This is a SIMS secondary ion mass spectrum and a schematic diagram of the x and y coordinates of a gallium nitride-based semiconductor laser with a divergence angle modulation layer as described in an embodiment of the present invention.

[0031] Figure 3 This is a SIMS secondary ion mass spectrum and a schematic diagram of x and y coordinates of the first divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention.

[0032] Figure 4 This is a SIMS secondary ion mass spectrum and a schematic diagram of x and y coordinates of the second divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention.

[0033] Figure 5 This is a TEM image of the first divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention.

[0034] Figure 6 This is a TEM image of the second divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention.

[0035] Figure 7 This is a SIMS-normalized Al atom concentration fitting diagram of the first divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention.

[0036] Figure 8 This is a SIMS-normalized Al atom concentration fitting diagram of the second divergence angle control layer of the gallium nitride-based semiconductor laser with a divergence angle modulation layer according to an embodiment of the present invention;

[0037] Figure 9 A comparison diagram of the horizontal divergence angles of a conventional green laser and a gallium nitride-based semiconductor laser with a divergence angle control layer according to an embodiment of the present invention;

[0038] Figure 10 A comparison diagram of the vertical divergence angles of a conventional green laser and a gallium nitride-based semiconductor laser with a divergence angle control layer according to an embodiment of the present invention;

[0039] Figure 11 This is a schematic diagram of the formation of a carrier lateral expansion region in the first divergence angle control layer of a gallium nitride-based semiconductor laser with a divergence angle control layer according to an embodiment of the present invention;

[0040] Figure 12 This is a schematic diagram of the second divergence angle control layer forming the carrier lateral expansion region in the gallium nitride-based semiconductor laser with a divergence angle control layer according to an embodiment of the present invention;

[0041] Figure 13 This is a schematic diagram showing the formation of a first refractive index depression region and a second refractive index depression region in the first divergence angle control layer and the second divergence angle control layer of the gallium nitride-based semiconductor laser with divergence angle control layer according to an embodiment of the present invention.

[0042] Figure label:

[0043] 100. Substrate; 101. Lower confinement layer; 102. Lower waveguide layer; 103. Active layer; 104. Upper waveguide layer; 105. Electron blocking layer; 106. Upper confinement layer; 107. Contact layer; 108. Divergence angle modulation layer.

[0044] 101a, First lower confinement layer; 101b, Second lower confinement layer; 101c, Third lower confinement layer;

[0045] 108a, First divergence angle modulation layer; 108b, Second divergence angle modulation layer. Detailed Implementation

[0046] 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.

[0047] like Figures 1 to 6As shown, this embodiment proposes a gallium nitride-based semiconductor laser with a divergence angle modulation layer, comprising, 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, an electron blocking layer 105, an upper confinement layer 106, and a contact layer 107. A divergence angle modulation layer 108 is also provided in this gallium nitride-based semiconductor laser with a divergence angle modulation layer.

[0048] Specifically, such as Figure 1 As shown, the gallium nitride-based semiconductor laser with a divergence angle modulation layer proposed in this embodiment 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, an electron blocking layer 105, an upper confinement layer 106, and a contact layer 107. The lower confinement layer 101 consists of three layers: 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.

[0049] The gallium nitride-based semiconductor laser also includes a divergence angle modulation layer 108. This divergence angle modulation layer 108 comprises a first divergence angle modulation layer 108a and a second divergence angle modulation layer 108b. The first divergence angle modulation layer 108a is disposed between the substrate 100 and the first lower confinement layer 101a, and the second divergence angle modulation layer 108b is disposed between the second lower confinement layer 101b and the third lower confinement layer 101c. Both the first divergence angle modulation layer 108a and the second divergence angle modulation layer 108b have a normalized Al atom concentration distribution.

[0050] Specifically, in this embodiment, the normalized Al atom concentration curves of the SIMS test of the first divergence angle modulation layer 108a and the second divergence angle modulation layer 108b both satisfy the Lorentz function distribution y=y0+(2A / π)×(w / (4×(xx)) c ) 2 +w 2 In this function, x is the independent variable, specifically the epitaxial layer thickness measured by SIMS, with the zero point representing the epitaxial layer surface. y is the dependent variable, namely the normalized Al atom concentration measured by SIMS. y0 is the baseline shift, where the baseline value of the function represents the background level below the peak, determining the vertical shift of the entire curve. cThe x-coordinate of the highest point of the peak (such as the "characteristic wavenumber" or "resonance frequency" of a spectral peak) is the core position parameter of the peak. w is the full width at half maximum (FWHM), which directly describes the "width" of the peak. The larger w is, the wider the peak is. A is the peak area (the integral area of ​​the peak), which is proportional to the concentration and content of the substance and is a key parameter for quantitative analysis.

[0051] In this embodiment, the lower confinement layer 101 in the gallium nitride-based semiconductor laser is designed as a three-layer structure. A first divergence angle modulation layer 108a is disposed between the substrate 100 and the first lower confinement layer 101a, and a second divergence angle modulation layer 108b is disposed between the second lower confinement layer 101b and the third lower confinement layer 101c. Furthermore, the normalized Al atom concentration curves of the SIMS tests of the first and second divergence angle modulation layers 108a and 108b both satisfy the Lorentz function distribution, thereby forming a carrier lateral expansion region between the first and second divergence angle modulation layers 108a and 108b. Figure 11 and Figure 12 As shown, enhancing the lateral expansion and mobility of charge carriers increases the recombination width of the active layer 103 in the horizontal divergence direction of the laser, thereby expanding the horizontal divergence angle, as... Figure 9 As shown, the horizontal divergence angle increased from 4-8° to 10-16°, and the mean angle increased from 6.6° to 12.7°, representing an increase of approximately 92.4% in the horizontal divergence angle.

[0052] In some alternative embodiments, such as Figure 7 As shown, in the normalized Al atom concentration curve function of the SIMS test of the first divergence angle modulation layer 108a: -0.08≤y0≤-0.02, 2≤x c ≤6, 0.005≤w≤0.5, 0.002≤A≤1.

[0053] Specifically, based on the above-mentioned constraints on the parameters in the function, combined with Figure 7 As shown in Table 1:

[0054] Table 1

[0055]

[0056] This embodiment illustrates several possible forms of the normalized Al atom concentration curve for the SIMS test of the first divergence angle modulation layer 108a, for example:

[0057] The function satisfies the Lorentz distribution: y = -0.05184 + (2 × 0.22353 / π) × (0.14804 / (4*(x - 4.04287)) 2+0.14804 2 ));

[0058] Alternatively, it may satisfy the Lorentz function distribution: y = -0.05184 + (2 × 0.2156 / π) × (0.01662 / (4*(x - 4.16629)) 2 +0.01662 2 ));

[0059] Alternatively, in special cases, the two function distribution curves mentioned above may overlap, forming y = -0.05184 + (2 × 0.22353 / π) × (0.14804 / (4*(x - 4.04287)). 2 +0.14804 2 ))-0.05184+(2×0.2156 / π)×(0.01662 / (4*(x-4.16629) 2 +0.01662 2 The function form of )).

[0060] like Figure 8 As shown, in the normalized Al atom concentration curve function of the SIMS test of the second divergence angle modulation layer 108b: -0.08≤y0≤-0.02, 1≤x c ≤5, 0.005≤w≤0.5, 0.005≤A≤0.5.

[0061] Specifically, based on the above-mentioned constraints on the parameters in the function, combined with Figure 8 As shown in Table 2:

[0062] Table 2

[0063]

[0064] This embodiment illustrates several possible forms of the normalized Al atom concentration curve for the SIMS test of the second divergence angle modulation layer 108b, for example:

[0065] The expression satisfies the Lorentz function distribution: y = -0.06864 + (2 × 0.0411 / π) × (0.02603 / (4 × (x - 2.32901)) 2 +0.02603 2 ));

[0066] Alternatively, it may satisfy the Lorentz function distribution: y = -0.06864 + (2 × 0.02228 / π) × (0.01685 / (4 × (x - 2.35916))) 2 +0.01685 2 ));

[0067] Alternatively, in special cases, the two function distribution curves mentioned above may overlap, forming y = -0.06864 + (2 × 0.0411 / π) × (0.02603 / (4*(x - 2.32901)). 2 +0.02603 2 ))-0.06864+(2×0.02228 / π)×(0.01685 / (4*(x-2.35916) 2 +0.01685 2 The function form of )).

[0068] In some optional embodiments, the reference offset of the first divergence angle modulation layer 108a is greater than or equal to the reference offset of the second divergence angle modulation layer 108b, the peak center position of the first divergence angle modulation layer 108a is greater than or equal to the peak center position of the second divergence angle modulation layer 108b, the full width at half maximum (FWHM) of the first divergence angle modulation layer 108a is greater than or equal to the full WHM of the second divergence angle modulation layer 108b, and the peak area of ​​the first divergence angle modulation layer 108a is greater than or equal to the peak area of ​​the second divergence angle modulation layer 108b.

[0069] This embodiment limits the parameters in the normalized Al atom concentration curve function of the first divergence angle modulation layer 108a and the second divergence angle modulation layer 108b, so that the first divergence angle modulation layer and the second divergence angle modulation layer respectively form a first refractive index depression region and a second refractive index depression region, such as... Figure 13 As shown, this creates a region with a rapid change in refractive index, causing the mode leakage of the laser substrate 100, which cannot be completely eliminated by the lower confinement layer 101, to be shielded and eliminated in two stages. This reduces the intensity of the mode leakage of the substrate 100, improving the far-field image quality (FFP) and spot quality of the laser, such as... Figure 10 As shown.

[0070] In some alternative embodiments, such as Figure 3 and Figure 5 As shown, the first divergence angle modulation layer 108a is any combination of GaN, AlGaN, AlInGaN, and AlN, and the thickness of the first divergence angle modulation layer 108a is from 5 angstroms to 800 angstroms.

[0071] In some alternative embodiments, such as Figure 4 and Figure 6 As shown, the second divergence angle modulation layer 108b is any combination of GaN, AlGaN, AlInGaN, AlN, and InGaN, and the thickness of the second divergence angle modulation layer 108b is from 5 angstroms to 500 angstroms.

[0072] In some alternative embodiments, the first lower confinement layer 101a is any combination of GaN, AlGaN, and AlN, the second lower confinement layer 101b is any combination of InGaN, GaN, and AlN, and the third lower confinement layer 101c is any combination of GaN, AlGaN, and AlN.

[0073] In some alternative embodiments, such as Figure 2 As shown, substrate 100 is a GaN single crystal substrate;

[0074] The lower waveguide layer 102 is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN;

[0075] The active layer 103 is an InGaN / GaN quantum well;

[0076] The upper waveguide layer 104 is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN;

[0077] The electron blocking layer 105 is any combination of AlGaN, GaN, InGaN, AlInGaN, or AlN.

[0078] The upper confinement layer 106 is any one of AlGaN or AlGaN / GaN or AlN / AlGaN / GaN or AlN / AlInGaN / AlGaN / GaN or AlInGaN / AlGaN / GaN;

[0079] The contact layer 107 is any combination of AlGaN, GaN, InGaN, and AlInGaN.

[0080] In some alternative embodiments, the lower waveguide layer 102 is a combination of GaN / InGaN, the upper waveguide layer 104 is a combination of InGaN / InGaN, the upper confinement layer 106 is a combination of AlGaN / AlGaN, the electron blocking layer 105 is a combination of AlN / AlGaN, and the contact layer 107 is GaN.

[0081] In some alternative embodiments, the thickness of the lower waveguide layer 102 is 300 Å to 8000 Å, the thickness of the upper waveguide layer 104 is 300 Å to 8000 Å, the thickness of the upper confinement layer 106 is 500 Å to 9000 Å, the thickness of the electron blocking layer 105 is 5 Å to 800 Å, and the thickness of the contact layer 107 is 5 Å to 2000 Å.

[0082] 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 with a divergence angle modulation layer, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, an upper confinement layer, and a contact 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. A first divergence angle modulation layer is disposed between the substrate and the first lower confinement layer, and a second divergence angle modulation layer is disposed between the second lower confinement layer and the third lower confinement layer. The normalized Al atom concentration curves of the first and second divergence angle modulation layers in SIMS tests both satisfy the Lorentz function distribution y = y0 + (2A / π) × (w / (4×(xx)) c ) 2 +w 2 In this context, x represents the epitaxial layer thickness measured by SIMS, zero is the epitaxial layer surface, y represents the normalized Al atom concentration measured by SIMS, y0 is the baseline offset, and x c Let w be the peak center position, w be the full width at half maximum (FWHM), and A be the peak area. In the normalized Al atom concentration curve function of the SIMS test of the first divergence angle modulation layer: -0.08≤y0≤-0.02, 2≤x c ≤6, 0.005≤w≤0.5, 0.002≤A≤1; In the normalized Al atom concentration curve function of the SIMS test of the second divergence angle modulation layer: -0.08≤y0≤-0.02, 1≤x c ≤5, 0.005≤w≤0.5, 0.005≤A≤0.

5.

2. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The reference offset of the first divergence angle modulation layer is greater than or equal to the reference offset of the second divergence angle modulation layer, the peak center position of the first divergence angle modulation layer is greater than or equal to the peak center position of the second divergence angle modulation layer, the full width at half maximum (FWHM) of the first divergence angle modulation layer is greater than or equal to the full width at half maximum (FWHM) of the second divergence angle modulation layer, and the peak area of ​​the first divergence angle modulation layer is greater than or equal to the peak area of ​​the second divergence angle modulation layer.

3. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The first divergence angle modulation layer is any combination of GaN, AlGaN, AlInGaN, and AlN, and the thickness of the first divergence angle modulation layer is from 5 angstroms to 800 angstroms.

4. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The second divergence angle modulation layer is any combination of GaN, AlGaN, AlInGaN, AlN, and InGaN, and the thickness of the second divergence angle modulation layer is from 5 angstroms to 500 angstroms.

5. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The first lower confinement layer is any combination of GaN, AlGaN, and AlN; the second lower confinement layer is any combination of InGaN, GaN, and AlN; and the third lower confinement layer is any combination of GaN, AlGaN, and AlN.

6. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The substrate is a GaN single crystal substrate; The lower waveguide layer is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN. The active layer is an InGaN / GaN quantum well; The upper waveguide layer is any one of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN. The electron blocking layer is any combination of AlGaN, GaN, InGaN, AlInGaN, or AlN. The upper confinement layer is any one of AlGaN or AlGaN / GaN or AlN / AlGaN / GaN or AlN / AlInGaN / AlGaN / GaN or AlInGaN / AlGaN / GaN. The contact layer is any combination of AlGaN, GaN, InGaN, and AlInGaN.

7. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The lower waveguide layer is a combination of GaN and InGaN, the upper waveguide layer is a combination of InGaN and InGaN, the upper confinement layer is a combination of AlGaN and AlGaN, the electron blocking layer is a combination of AlN and AlGaN, and the contact layer is GaN.

8. The gallium nitride-based semiconductor laser with a divergence angle modulation layer according to claim 1, characterized in that, The thickness of the lower waveguide layer is 300 Å to 8000 Å, the thickness of the upper waveguide layer is 300 Å to 8000 Å, the thickness of the upper confinement layer is 500 Å to 9000 Å, the thickness of the electron blocking layer is 5 Å to 800 Å, and the thickness of the contact layer is 5 Å to 2000 Å.

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