Gallium nitride-based semiconductor laser with gradient hole mobility waveguide layer

Abstract

According to the gallium nitride-based semiconductor laser with the gradually-changed hole mobility waveguide layer, a fitting curve of In ion strength distribution or In atom concentration distribution, a fitting curve of valence band effective state density distribution and a fitting curve of hole mobility distribution of an upper waveguide layer and a lower waveguide layer which are tested by SIMS all meet any function distribution of ExpGrow1, ExpGrow2, Lorentz and Bradley; energy band degeneracy is improved, ionization impurities, polarization charges and energy band bending restriction are reduced, coupling of a heavy hole band and a light hole band with an SO band is regulated and controlled, valence band effective state density is improved, population inversion and laser gain are enhanced, hole mobility distribution of a waveguide layer is controlled to be in splayed distribution, interface scattering and ionization impurity scattering are inhibited, and the performance of the laser is improved. The hole mobility and the thermal stability are improved, the hole transport efficiency is enhanced, the hole leakage is reduced, and the slope efficiency, the optical power, the aging life and the temperature quenching ratio of the laser are improved.

Description

A gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer Technical Field

[0001] This application relates to the field of semiconductor optoelectronic devices, and more particularly to a gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer. 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 generated by spontaneous emission. 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 the active layer or pn junction under the action of external voltage to generate radiative recombination, while lasers 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: the hole concentration in the p-type semiconductor is much lower than the electron concentration, and the hole mobility is much lower than the electron mobility. Furthermore, the quantum well polarization field raises the hole injection barrier, leading to hole overflow from the active layer. This results in uneven and inefficient hole injection, causing severe electron-hole asymmetry and mismatch in the quantum well, electron leakage, and carrier delocalization. Hole transport within the quantum well becomes more difficult, and the uneven carrier injection leads to gain non-uniformity. Simultaneously, the laser gain spectrum broadens, and the peak gain decreases, resulting in increased threshold current and reduced slope efficiency. When electrons leak into the p-type semiconductor, a bipolar conductance effect occurs. Even with active layer carrier concentration saturation, the junction voltage at the threshold voltage saturates, but the series resistance increases, leading to a rise in the total laser voltage. Summary of the Invention

[0009] To address one of the aforementioned technical problems, this invention provides a gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer.

[0010] This invention provides a gallium nitride-based semiconductor laser with a graded hole mobility waveguide 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, and an upper confinement layer, wherein the upper waveguide layer is a graded hole mobility upper waveguide layer, and the lower waveguide layer is a graded hole mobility lower waveguide layer;

[0011] The fitting curves of the In ion intensity distribution or In atom concentration distribution, the fitting curve of the valence band effective state density distribution, and the fitting curve of the hole mobility distribution of the waveguide layer with the gradient hole mobility all satisfy any one of the function distributions of ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0012] The fitting curves of the In ion intensity distribution or In atom concentration distribution, the fitting curve of the valence band effective state density distribution, and the fitting curve of the hole mobility distribution of the waveguide layer under the gradient hole mobility test all satisfy any one of the function distributions of ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0013] Preferably, when the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer with graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y1=B+A*exp((x1-C) / D), where B is the baseline or asymptotic value, A is the magnitude of the exponential term, C is the characteristic position parameter, D is the characteristic rate parameter, y1 is the SIMS test In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 is the thickness of the waveguide layer with graded hole mobility, wherein: -2E26≤B≤0, 7E15≤A≤7E26, ​​-150≤C≤150, 0.002≤D≤200;

[0014] When the fitting curves of the In ion intensity distribution or In atom concentration distribution in the SIMS test of the waveguide layer with the graded hole mobility satisfy the ExpGrow2 function distribution, the ExpGrow2 function is y2=E+F1*exp((x1-G1) / H1)+F2*exp((x1-G2 / H2), where E is the baseline or asymptotic value, F1 is the amplitude of branch 1, G1 is the characteristic position of branch 1, H1 is the rate parameter of branch 1, F1 is the amplitude of branch 2, G1 is the characteristic position of branch 2, and H1 is the characteristic position of branch 2. Rate parameters, y2 is the SIMS measured In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, x1 is the thickness of the waveguide layer with graded hole mobility, where: -2E26≤E≤0, 5E15≤F1≤5E26, 5E15≤F2≤5E26, -60≤G1≤60, -60≤G2≤60, 0.002≤H1≤200, 0.002≤H2≤200;

[0015] When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer with graded hole mobility satisfies the Lorentz function distribution, the Lorentz function is y3=J+(2*K / π)*(L / (4*(x1-M)^2+L^2)), where J is the baseline background value, K is the peak term integral intensity, L is the half width at half maximum (FWHM), M is the peak position, y3 is the SIMS test In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 is the thickness of the waveguide layer with graded hole mobility, where: -2E26≤J≤0, 6E15≤K≤6E26, 0.006≤L≤60, 0.006≤M≤60;

[0016] When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer with graded hole mobility satisfies the Bradley function distribution, the Bradley function is y4=N*ln(-P*ln(x1)), where N is the scaling factor, P is the threshold parameter, y4 is the SIMS test In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 is the thickness of the waveguide layer with graded hole mobility, where: -5E25≤N≤0, 0.009≤P≤900.

[0017] Preferably, when the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y5=Q+R*exp((x2-S) / T), where Q is the baseline or asymptotic value, R is the magnitude of the exponential term, S is the characteristic position parameter, T is the characteristic rate parameter, y5 is the SIMS test In ion intensity or In atom concentration of the waveguide layer under the graded hole mobility, and x2 is the thickness of the waveguide layer under the graded hole mobility, wherein: 4E15≤Q≤4E30, -2E30≤R≤0, -500000≤S≤0, 200≤T≤200000;

[0018] When the fitting curves of the In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility in SIMS testing satisfy the ExpGrow2 function distribution, the ExpGrow2 function is y6=U+V1*exp((x2-W1) / Z1)+V2*exp((x2-W2 / Z2), where U is the baseline or asymptotic value, V1 is the amplitude of branch 1, W1 is the characteristic position of branch 1, Z1 is the rate parameter of branch 1, V2 is the amplitude of branch 2, W2 is the characteristic position of branch 2, and Z2 is the characteristic position of branch 2. The rate parameter, y6, is the SIMS test In ion intensity or In atom concentration of the waveguide layer under graded hole mobility, and x2 is the waveguide layer thickness under graded hole mobility, where: 5E15≤U≤4E31, -1E30≤V1≤0, -1E30≤V2≤0, -100000≤W1≤100, -100000≤W2≤100, 20≤Z1≤20000, 20≤Z2≤20000;

[0019] When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility satisfies the Lorentz function distribution, the Lorentz function is y7=b+(2*a / π)*(c / (4*(x2-d)^2+c^2)), b is the baseline background value, a is the peak term integral intensity, c is the half width at half maximum (FWHM), d is the peak position, y7 is the SIMS test In ion intensity or In atom concentration of the waveguide layer under the graded hole mobility, and x2 is the waveguide layer thickness under the graded hole mobility, where: -2E26≤b≤0, 6E15≤a≤6E26, 0.002≤c≤20, 0.0001≤d≤10;

[0020] When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y8=f*ln(-g*ln(x2)), where f is the scaling factor, g is the threshold parameter, y8 is the SIMS test In ion intensity or In atom concentration of the waveguide layer under the graded hole mobility, and x2 is the thickness of the waveguide layer under the graded hole mobility, where: 3E15≤f≤3E25, 0.05≤g≤500.

[0021] Preferably, when the fitting curve of the valence band effective density of states distribution of the waveguide layer with the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y9=h+i*exp((x1-j) / k), where h is the baseline or asymptotic value, i is the magnitude of the exponential term, j is the characteristic position parameter, k is the characteristic rate parameter, y9 is the valence band effective density of states of the waveguide layer with the graded hole mobility, and x1 is the thickness of the waveguide layer with the graded hole mobility, wherein: 3E14≤h≤3E25, 3E13≤i≤3E23, -100≤j≤0, 0.001≤k≤100;

[0022] When the fitted curve of the valence band effective density of states distribution of the waveguide layer at the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 10 =m*ln(-n*ln(x1)), where m is the scaling factor, n is the threshold parameter, and y 10 Let x1 be the effective density of states in the valence band of the waveguide layer with graded hole mobility, and let x1 be the thickness of the waveguide layer with graded hole mobility, where: -2E25≤m≤0, 4E-15≤n≤4E-5.

[0023] Preferably, when the fitted curve of the valence band effective density of states distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 11=p+q*exp((x2-r) / s), where p is the baseline or asymptotic value, q is the magnitude of the exponential term, r is the characteristic location parameter, s is the characteristic rate parameter, and y 11 denoted as valence band effective density of states of the waveguide layer under graded hole mobility, and x2 as the thickness of the waveguide layer under graded hole mobility, where: 2E16≤p≤2E30, -6E30≤q≤0, -30000≤r≤0, 20≤s≤20000;

[0024] When the fitted curve of the valence band effective state density distribution of the waveguide layer under the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 12 =t*ln(-u*ln(x2)), where t is the scaling factor, u is the threshold parameter, and y 12 x1 represents the effective density of states in the valence band of the waveguide layer under graded hole mobility, and x2 represents the thickness of the waveguide layer under graded hole mobility, where: 1E13≤t≤1E25, 6E10≤t≤6E20.

[0025] Preferably, when the fitted curve of the hole mobility distribution of the waveguide layer with the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 13 =v+w*exp((x1-z) / o), where v is the baseline or asymptotic value, w is the magnitude of the exponential term, z is the characteristic position parameter, o is the characteristic rate parameter, and y is the characteristic velocity parameter. 13 Let be the effective density of states in the valence band of the waveguide layer with graded hole mobility, and x1 be the thickness of the waveguide layer with graded hole mobility, where: -70000≤v≤0, 20≤w≤20000, -1000≤z≤1000, 0.001≤o≤100;

[0026] When the fitted curve of the hole mobility distribution of the waveguide layer with the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 14 =F3*ln(-G3*ln(x1)), where F3 is the scaling factor, G3 is the threshold parameter, and y 14 Let F be the effective density of states in the valence band of the waveguide layer with graded hole mobility, and let x1 be the thickness of the waveguide layer with graded hole mobility, where: -20000≤F3≤200, 0.0008≤G3≤800.

[0027] Preferably, when the fitted curve of the valence band effective density of states distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 15 =H3+J3*exp((x2-K3) / L3), where H3 is the baseline or asymptotic value, J3 is the magnitude of the exponential term, K3 is the characteristic position parameter, L3 is the characteristic rate parameter, and y15 x2 is the effective density of states in the valence band of the waveguide layer under the graded hole mobility, and x3 is the thickness of the waveguide layer under the graded hole mobility, where: 1E2≤H3≤1E12, -500000000≤J3≤0, -20000≤K3≤200, 20≤L3≤200000;

[0028] When the fitted curve of the valence band effective state density distribution of the waveguide layer under the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 16 =M3*ln(-P3*ln(x2)), where M3 is the scaling factor, P3 is the threshold parameter, and y 16 denoted as M3, where M3 represents the effective density of states in the valence band of the waveguide layer under graded hole mobility, and x2 represents the thickness of the waveguide layer under graded hole mobility, where: 10 ≤ M3 ≤ 10000, 0.007 ≤ P3 ≤ 7000.

[0029] Preferably, the substrate is a GaN single crystal substrate.

[0030] Preferably, the lower waveguide layer is any one or any combination of InGaN or GaN / InGaN or GaN / InGaN / GaN or InGaN / GaN or GaN, with a thickness of 300 angstroms to 8000 angstroms;

[0031] The active layer is an InGaN / GaN quantum well;

[0032] The upper waveguide layer is any one or any combination of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN, with a thickness of 300 angstroms to 8000 angstroms.

[0033] Preferably, the electron blocking layer is any one or any combination of AlGaN, GaN, InGaN, AlInGaN, and AlN, with a thickness of 5 angstroms to 800 angstroms;

[0034] The upper confinement layer is any one or any combination of AlGaN, AlN, GaN, AlInN, and AlInGaN, with a thickness of 500 angstroms to 9000 angstroms;

[0035] The lower confinement layer is any one or any combination of AlGaN, GaN, AlN, InGaN, AlInGaN, and AlInN, with a thickness of 5,000 angstroms to 50,000 angstroms.

[0036] The beneficial effects of this invention are as follows: In this invention, the upper and lower waveguide layers of the gallium nitride-based semiconductor laser are respectively a graded-variable hole mobility upper waveguide layer and a graded-variable hole mobility lower waveguide layer. The fitting curves of the In ion intensity distribution or In atom concentration distribution, the fitting curve of the valence band effective state density distribution, and the fitting curve of the hole mobility distribution in the SIMS tests of the graded-variable hole mobility upper and lower waveguide layers all satisfy any one of the ExpGrow1, ExpGrow2, Lorentz, or Bradley function distributions. Through the upper waveguide layer and... The design of the effective density of states distribution in the valence band of the lower waveguide layer integrates quantum confinement, strain engineering, and heterostructure design to improve band degeneracy, reduce ionization impurities, polarization charge, and band bending constraints, regulate the coupling of the heavy hole band and light hole band with the SO band, increase the effective density of states in the valence band, enhance population inversion and laser gain, and thus control the hole mobility distribution in the waveguide layer to an "octagonal" shape, suppress interface scattering and ionization impurity scattering, improve hole mobility and thermal stability, enhance hole transport efficiency, reduce hole leakage, and improve laser slope efficiency, optical power, aging lifetime, and temperature quenching ratio. Attached Figure Description

[0037] 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:

[0038] Figure 1 is a schematic diagram of the structure of a gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to an embodiment of the present invention.

[0039] Figure 2 is a SIMS secondary ion mass spectrum and a schematic diagram of x and y coordinates of a gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to an embodiment of the present invention.

[0040] Figure 3 is a graph showing the In ion intensity distribution or In atom concentration distribution of the gradient hole mobility waveguide layer of the gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer according to an embodiment of the present invention, and its ExpGrow1 fitting curve.

[0041] Figure 4 shows the In ion intensity distribution or In atom concentration distribution of the gradient hole mobility waveguide layer of the gallium nitride-based semiconductor laser with gradient hole mobility waveguide layer according to the embodiment of the present invention, and its ExpGrow2 fitting curve.

[0042] Figure 5 shows the In ion intensity distribution or In atom concentration distribution of the gradient hole mobility waveguide layer of the gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer according to an embodiment of the present invention, and its Lorentz fitting curve.

[0043] Figure 6 shows the In ion intensity distribution or In atom concentration distribution of the gradient hole mobility waveguide layer of the gallium nitride-based semiconductor laser with the gradient hole mobility waveguide layer according to the embodiment of the present invention, and its Bradley fitting curve.

[0044] Figure 7 shows the In ion intensity distribution or In atom concentration distribution of the waveguide layer with a graded hole mobility waveguide layer according to the embodiment of the present invention, and its ExpGrow1 fitting curve.

[0045] Figure 8 shows the In ion intensity distribution or In atom concentration distribution of the waveguide layer with a graded hole mobility waveguide layer according to the embodiment of the present invention, and its ExpGrow2 fitting curve.

[0046] Figure 9 shows the In ion intensity distribution or In atom concentration distribution of the waveguide layer with a graded hole mobility waveguide layer according to the embodiment of the present invention, and its Lorentz fitting curve.

[0047] Figure 10 shows the In ion intensity distribution or In atom concentration distribution of the waveguide layer with a graded hole mobility waveguide layer according to the embodiment of the present invention, and its Bradley fitting curve.

[0048] Figure 11 shows the valence band effective state density distribution of the waveguide layer with graded hole mobility and its ExpGrow1 fitting curve of the gallium nitride-based semiconductor laser with graded hole mobility waveguide layer according to the embodiment of the present invention.

[0049] Figure 12 shows the valence band effective state density distribution of the waveguide layer with graded hole mobility of the gallium nitride-based semiconductor laser with graded hole mobility waveguide layer according to the embodiment of the present invention and its Bradley fitting curve.

[0050] Figure 13 is a graph showing the hole mobility distribution of the waveguide layer and its ExpGrow1 fitting curve of the gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer according to an embodiment of the present invention.

[0051] Figure 14 is a graph showing the hole mobility distribution of the waveguide layer and its Bradley fitting curve of the gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer according to an embodiment of the present invention.

[0052] Figure 15 shows the distribution of the effective state density of the valence band of the waveguide layer and its ExpGrow1 fitting curve under the graded hole mobility of the gallium nitride-based semiconductor laser with graded hole mobility layer according to the embodiment of the present invention.

[0053] Figure 16 shows the distribution of the effective state density of the valence band of the waveguide layer of the gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to the embodiment of the present invention, and its Bradley fitting curve.

[0054] Figure 17 shows the hole mobility distribution of the waveguide layer and its ExpGrow1 fitting curve of the gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to the embodiment of the present invention.

[0055] Figure 18 shows the hole mobility distribution of the waveguide layer and its Bradley fitting curve of the gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to the embodiment of the present invention.

[0056] Figure 19 is a diagram showing the hole mobility distribution of the upper and lower waveguide layers of the gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to an embodiment of the present invention.

[0057] Figure label:

[0058] 100. Substrate; 101. Lower confinement layer; 102. Lower waveguide layer with graded hole mobility; 103. Active layer; 104. Upper waveguide layer with graded hole mobility; 105. Electron blocking layer; 106. Upper confinement layer. Detailed Implementation

[0059] 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.

[0060] As shown in Figures 1 and 2, this embodiment proposes a gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer, comprising a substrate 100, a lower confinement layer 101, a lower waveguide layer, an active layer 103, an upper waveguide layer, an electron blocking layer 105, and an upper confinement layer 106 arranged sequentially from bottom to top.

[0061] Specifically, in this embodiment, the gallium nitride-based semiconductor laser is provided from bottom to top with a substrate 100, a lower confinement layer 101, a lower waveguide layer, an active layer 103, an upper waveguide layer, an electron blocking layer 105, and an upper confinement layer 106. The upper waveguide layer is a graded hole mobility upper waveguide layer 104, and the lower waveguide layer is a graded hole mobility lower waveguide layer 102. Both the graded hole mobility upper waveguide layer 104 and the graded hole mobility lower waveguide layer 102 exhibit In ion intensity distribution or In atom concentration distribution, valence band effective state density distribution, and hole mobility distribution characteristics, specifically manifested as follows:

[0062] The fitting curves of the In ion intensity distribution or In atom concentration distribution of the waveguide layer 104 with graded hole mobility in SIMS test satisfy any one of the following function distributions: ExpGrow1 (exponential growth function type 1), ExpGrow2 (double exponential growth or decay model), Lorentz (Lorentz function distribution), and Bradley (log-log transform nonlinear model).

[0063] The fitting curve of the effective density of states distribution in the valence band of waveguide layer 104 with graded hole mobility satisfies any one of the function distributions ExpGrow1, ExpGrow2, Lorentz, or Bradley.

[0064] The fitted curve of the hole mobility distribution of the waveguide layer 104 with gradient hole mobility satisfies any one of the function distributions ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0065] The fitting curves of the In ion intensity distribution or In atom concentration distribution of waveguide layer 102 under graded hole mobility SIMS test satisfy any one of the function distributions ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0066] The fitting curve of the effective density of states distribution in the valence band of waveguide layer 102 under graded hole mobility satisfies any one of the function distributions ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0067] The fitted curve of the hole mobility distribution of waveguide layer 102 under graded hole mobility satisfies any one of the function distributions ExpGrow1, ExpGrow2, Lorentz, and Bradley.

[0068] More specifically, the fitting curves for the In ion intensity distribution or In atom concentration distribution of the SIMS test of the upper waveguide layer 104 and the lower waveguide layer 102 with graded hole mobility can be any of the following combinations: ExpGrow1 and ExpGrow1 combination, ExpGrow2 and ExpGrow2 combination, Lorentz and Lorentz combination, Bradley and Bradley combination, ExpGrow1 and ExpGrow2 combination, ExpGrow1 and Lorentz combination, ExpGrow1 and Bradley combination, ExpGrow2 and Lorentz combination, ExpGrow2 and Bradley combination, ExpGrow2 and ExpGrow1 combination, Lorentz and ExpGrow1 combination, Lorentz and ExpGrow2 combination, Lorentz and Bradley combination, Bradley and ExpGrow1 combination, Bradley and ExpGrow2 combination, Bradley and Lorentz combination.

[0069] The effective density of states in the valence band of the graded hole mobility upper waveguide layer 104 and the graded hole mobility lower waveguide layer 102 can be any of the following combinations: ExpGrow1 and ExpGrow1 combination, ExpGrow2 and ExpGrow2 combination, Lorentz and Lorentz combination, Bradley and Bradley combination, ExpGrow1 and ExpGrow2 combination, ExpGrow1 and Lorentz combination, ExpGrow1 and Bradley combination, ExpGrow2 and Lorentz combination, ExpGrow2 and Bradley combination, ExpGrow2 and ExpGrow1 combination, Lorentz and ExpGrow1 combination, Lorentz and ExpGrow2 combination, Lorentz and Bradley combination, Bradley and ExpGrow1 combination, Bradley and ExpGrow2 combination, Bradley and Lorentz combination.

[0070] The hole mobility distributions of the upper waveguide layer 104 and the lower waveguide layer 102 with graded hole mobility can be any of the following combinations: ExpGrow1 and ExpGrow1 combination, ExpGrow2 and ExpGrow2 combination, Lorentz and Lorentz combination, Bradley and Bradley combination, ExpGrow1 and ExpGrow2 combination, ExpGrow1 and Lorentz combination, ExpGrow1 and Bradley combination, ExpGrow2 and Lorentz combination, ExpGrow2 and Bradley combination, ExpGrow2 and ExpGrow1 combination, Lorentz and ExpGrow1 combination, Lorentz and ExpGrow2 combination, Lorentz and Bradley combination, Bradley and ExpGrow1 combination, Bradley and ExpGrow2 combination, Bradley and Lorentz combination.

[0071] In some optional embodiments, when the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer 104 with gradient hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function distribution satisfied by the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer 104 with gradient hole mobility is y1=B+A*exp((x1-C) / D), the core feature of which is exponential monotonic change. The baseline level, growth amplitude, characteristic position and change rate of the curve are controlled by four parameters, which can be applied to the control of the dynamic process, signal response and material growth of GaN lasers. In this function, B is the baseline or asymptotic value (the basic response value when the contribution of the exponential term is 0), A is the magnitude of the exponential term (the maximum potential magnitude of the exponential change (growth type) or the initial offset magnitude (decay type)), C is the characteristic position parameter, D is the characteristic rate parameter (the rate controlling the exponential change), y1 is the SIMS measured In ion strength or In atom concentration of waveguide layer 104 with graded hole mobility, and x1 is the thickness of waveguide layer 104 with graded hole mobility, where: -2E26≤B≤0, 7E15≤A≤7E26, ​​-150≤C≤150, 0.002≤D≤200. As shown in Figure 3, the ExpGrow1 function can be specifically defined as y1=-2.18933E21+7.45456E20*exp((x1+1.35347) / 1.57109).

[0072] When the fitting curves of the In ion intensity distribution or In atom concentration distribution in the SIMS test of waveguide layer 104 with graded hole mobility satisfy the ExpGrow2 function distribution, the ExpGrow2 function is y2=E+F1*exp((x1-G1) / H1)+F2*exp((x1-G2 / H2). Its core feature is the linear superposition of two independent exponential processes, which can describe the dynamic response of the GaN laser under multi-mechanism coupling. In this function, E is the baseline or asymptotic value (the basic response value when the contribution of the exponential term is 0), F1 is the amplitude of branch 1, G1 is the characteristic position of branch 1, H1 is the rate parameter of branch 1, F1 is the amplitude of branch 2, G1 is the characteristic position of branch 2, and H1 is the amplitude of branch 2. The rate parameter y2 represents the SIMS measured In ion strength or In atom concentration of waveguide layer 104 with graded hole mobility, and x1 represents the thickness of waveguide layer 104 with graded hole mobility, where: -2E26≤E≤0, 5E15≤F1≤5E26, 5E15≤F2≤5E26, -60≤G1≤60, -60≤G2≤60, 0.002≤H1≤200, 0.002≤H2≤200. As shown in Figure 4, the ExpGrow2 function can be specifically defined as y2=-2.18933E21+5.88698E20*exp((x1+0.63538) / 1.57107)+5.88698E20*exp((x1+0.63538) / 1.5711).

[0073] When the fitting curve of the In ion intensity distribution or In atom concentration distribution of the SIMS test of the waveguide layer 104 with graded hole mobility satisfies the Lorentz function distribution, the Lorentz function is y3=J+(2*K / π)*(L / (4*(x1-M)^2+L^2)), where J is the baseline background value (the basic response value when the peak term contribution is 0), K is the peak term integral intensity (the total area of ​​the peak term (integral value), reflecting the total signal intensity), L is the full width at half maximum (FWHM), M is the peak position, y3 is the In ion intensity or In atom concentration of the waveguide layer 104 with graded hole mobility in SIMS test, and x1 is the thickness of the waveguide layer 104 with graded hole mobility, where: -2E26≤J≤0, 6E15≤K≤6E26, 0.006≤L≤60, 0.006≤M≤60. As shown in Figure 5, the Lorentz function can be specifically y3=-3.33798E20+(2 / 6.76154E20 / π)*(0.58801 / (4*(x1-0.65514)^2+0.55801^2)).

[0074] When the fitted curves of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer 104 with graded hole mobility satisfy the Bradley function distribution, the Bradley function is y4=N*ln(-P*ln(x1)), where N is the scaling factor (controlling the overall scaling and response direction of the function), P is the threshold parameter, y4 is the SIMS test In ion intensity or In atom concentration of the waveguide layer 104 with graded hole mobility, and x1 is the thickness of the waveguide layer 104 with graded hole mobility, where: -5E25≤N≤0, 0.009≤P≤900. As shown in Figure 6, the Bradley function can specifically be y4=-5.32495E20*ln(-0.92689*ln(x1)).

[0075] In some optional embodiments, when the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of waveguide layer 102 under graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y5=Q+R*exp((x2-S) / T), where Q is the baseline or asymptotic value, R is the magnitude of the exponential term, S is the characteristic position parameter, T is the characteristic rate parameter, y5 is the SIMS test In ion intensity or In atom concentration of waveguide layer 102 under graded hole mobility, and x2 is the thickness of waveguide layer 102 under graded hole mobility, where: 4E15≤Q≤4E30, -2E30≤R≤0, -500000≤S≤0, 200≤T≤200000. As shown in Figure 7, the ExpGrow1 function can be specifically defined as y5 = 4.69587E24 - 1.72514E24 * exp((x2 + 2829.93508) / 2826.88553).

[0076] When the fitting curves of the In ion intensity distribution or In atom concentration distribution in waveguide layer 102 under SIMS testing at graded hole mobility satisfy the ExpGrow2 function distribution, the ExpGrow2 function is y6=U+V1*exp((x2-W1) / Z1)+V2*exp((x2-W2 / Z2), where U is the baseline or asymptotic value, V1 is the amplitude of branch 1, W1 is the characteristic position of branch 1, Z1 is the rate parameter of branch 1, V2 is the amplitude of branch 2, W2 is the characteristic position of branch 2, and Z2 is the characteristic position of branch 2. The rate parameter y6 represents the SIMS measured In ion strength or In atom concentration of waveguide layer 102 under graded hole mobility, and x2 represents the thickness of waveguide layer 102 under graded hole mobility, where: 5E15≤U≤4E31, -1E30≤V1≤0, -1E30≤V2≤0, -100000≤W1≤100, -100000≤W2≤100, 20≤Z1≤20000, 20≤Z2≤20000. As shown in Figure 8, the ExpGrow2 function can be specifically defined as follows:

[0077] y6=4.04161E24-1.2226E24*exp((x2+1219.91781) / 2432.86046)-1.22447E24*exp((x2+1219.91781) / 2433.15506).

[0078] When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of waveguide layer 102 under graded hole mobility satisfies the Lorentz function distribution, the Lorentz function is y7=b+(2*a / π)*(c / (4*(x2-d)^2+c^2)), b is the baseline background value, a is the peak term integral intensity, c is the half width at half maximum (FWHM), d is the peak position, y7 is the SIMS test In ion intensity or In atom concentration of waveguide layer 102 under graded hole mobility, and x2 is the thickness of waveguide layer 102 under graded hole mobility, where: -2E26≤b≤0, 6E15≤a≤6E26, 0.002≤c≤20, 0.0001≤d≤10. As shown in Figure 9, the Lorentz function can be specifically expressed as y7 = -1.25883E21 + (2 * 6.6177E21 / π) * (1.7114 / (4 * (x2 - 0.01151)^2 + 1.7114^2)).

[0079] When the fitting curves of the SIMS test In ion intensity distribution or In atom concentration distribution of waveguide layer 102 under graded hole mobility satisfy the Bradley function distribution, the Bradley function is y8=f*ln(-g*ln(x2)), where f is the scaling factor, g is the threshold parameter, y8 is the SIMS test In ion intensity or In atom concentration of waveguide layer 102 under graded hole mobility, and x2 is the thickness of waveguide layer 102 under graded hole mobility, where: 3E15≤f≤3E25, 0.05≤g≤500. As shown in Figure 10, the Bradley function can be specifically y8=3.66858E20*ln(-5.47919*ln(x2)).

[0080] In some optional embodiments, when the fitted curve of the effective density of states in the valence band of the waveguide layer 104 with the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y9=h+i*exp((x1-j) / k), where h is the baseline or asymptotic value, i is the magnitude of the exponential term, j is the characteristic position parameter, k is the characteristic rate parameter, y9 is the effective density of states in the valence band of the waveguide layer 104 with the graded hole mobility, and x1 is the thickness of the waveguide layer 104 with the graded hole mobility, where: 3E14≤h≤3E25, 3E13≤i≤3E23, -100≤j≤0, 0.001≤k≤100. As shown in Figure 11, the ExpGrow1 function can specifically be y9=3.71815E19+3.00266E18*exp((x1+1.35347) / 1.57109).

[0081] When the fitted curve of the effective density of states in the valence band of waveguide layer 104 with graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 10 =m*ln(-n*ln(x1)), where m is the scaling factor, n is the threshold parameter, and y 10 Let be the effective density of states in the valence band of the graded-hole-mobility waveguide layer 104, and let x1 be the thickness of the graded-hole-mobility waveguide layer 104, where -2E25 ≤ m ≤ 0, 4E-15 ≤ n ≤ 4E-5. As shown in Figure 12, this Bradley function can be specifically expressed as y 10 =-2.14486E18*ln(-4.49676E-10)*ln(x1)).

[0082] In some optional embodiments, when the fitted curve of the effective density of states distribution in the valence band of waveguide layer 102 under graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 11=p+q*exp((x2-r) / s), where p is the baseline or asymptotic value, q is the magnitude of the exponential term, r is the characteristic location parameter, s is the characteristic rate parameter, and y 11 Let be the effective density of states in the valence band of waveguide layer 102 under graded hole mobility, and let x2 be the thickness of waveguide layer 102 under graded hole mobility, where: 2E16≤p≤2E30, -6E30≤q≤0, -30000≤r≤0, 20≤s≤20000. As shown in Figure 13, the ExpGrow1 function can be specifically defined as y 11 =1.64618E22-6.03553E21*exp((x2+2729.89049) / 2729.15653).

[0083] When the fitted curve of the effective density of states in the valence band of waveguide layer 102 under graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 12 =t*ln(-u*ln(x2)), where t is the scaling factor, u is the threshold parameter, and y 12 Let y1 be the effective density of states in the valence band of waveguide layer 102 under graded hole mobility, and x2 be the thickness of waveguide layer 102 under graded hole mobility, where: 1E13 ≤ t ≤ 1E25, 6E10 ≤ t ≤ 6E20. As shown in Figure 14, this Bradley function can be specifically defined as y1. 12 =1.32838E18*ln(-5.99467E15*ln(x2)).

[0084] In some alternative embodiments, when the fitted curve of the hole mobility distribution of the waveguide layer 104 with gradient hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 13 =v+w*exp((x1-z) / o), where v is the baseline or asymptotic value, w is the magnitude of the exponential term, z is the characteristic position parameter, o is the characteristic rate parameter, and y is the characteristic velocity parameter. 13 Let be the effective density of states in the valence band of the waveguide layer 104 with graded hole mobility, and let x1 be the thickness of the waveguide layer 104 with graded hole mobility, where: -70000≤v≤0, 20≤w≤20000, -1000≤z≤1000, 0.001≤o≤100. As shown in Figure 15, the ExpGrow1 function can be specifically defined as y 13 =-738.46961+261.66029*exp((x1+1.35347) / 1.57109).

[0085] When the fitted curve of the hole mobility distribution of waveguide layer 104 with graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 14=F3*ln(-G3*ln(x1)), where F3 is the scaling factor, G3 is the threshold parameter, and y 14 Let be the effective density of states in the valence band of the graded-homogeneous hole mobility waveguide layer 104, and let x1 be the thickness of the graded-homogeneous hole mobility waveguide layer 104, where -20000≤F3≤200, 0.0008≤G3≤800. As shown in Figure 16, the Bradley function can be specifically defined as y 14 =-186.90966*ln(-0.78944*ln(x1)).

[0086] In some optional embodiments, when the fitted curve of the effective density of states distribution in the valence band of waveguide layer 102 under graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 15 =H3+J3*exp((x2-K3) / L3), where H3 is the baseline or asymptotic value, J3 is the magnitude of the exponential term, K3 is the characteristic position parameter, L3 is the characteristic rate parameter, and y 15 Let y1 be the effective density of states in the valence band of waveguide layer 102 under graded hole mobility, and x2 be the thickness of waveguide layer 102 under graded hole mobility, where: 1E2≤H3≤1E12, -500000000≤J3≤0, -20000≤K3≤200, and 20≤L3≤200000. As shown in Figure 17, the ExpGrow1 function can be specifically defined as y1. 15 =1.43202E6-526364.49505*exp((x2+2733.3889) / 2731.97204).

[0087] When the fitted curve of the effective density of states in the valence band of waveguide layer 102 under graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 16 =M3*ln(-P3*ln(x2)), where M3 is the scaling factor, P3 is the threshold parameter, and y 16 Let be the effective density of states in the valence band of waveguide layer 102 under graded hole mobility, and let x2 be the thickness of waveguide layer 102 under graded hole mobility, where: 10 ≤ M3 ≤ 10000, 0.007 ≤ P3 ≤ 7000. As shown in Figure 18, the Bradley function can be specifically expressed as y 16 =115.75868*ln(-7.10016*ln(x2)).

[0088] As shown in Figure 19, in this embodiment, the hole mobility of the upper waveguide layer 104 and the lower waveguide layer 102 with the gradient hole mobility forms an "eight"-shaped distribution, which suppresses interface scattering and ionized impurity scattering, improves hole mobility and thermal stability, enhances hole transport efficiency, reduces hole leakage, and improves laser slope efficiency, optical power, aging lifetime, and temperature quenching ratio.

[0089] In some alternative embodiments, the substrate 100 is a GaN single crystal substrate 100.

[0090] The lower waveguide layer is any one or any combination of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN, with a preferred combination of GaN / InGaN, and has a thickness of 300 angstroms to 8000 angstroms.

[0091] The active layer 103 is an InGaN / GaN quantum well.

[0092] The upper waveguide layer is any one or any combination of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN, preferably InGaN, and has a thickness of 300 angstroms to 8000 angstroms.

[0093] The electron blocking layer 105 is any one or any combination of AlGaN, GaN, InGaN, AlInGaN, and AlN, preferably AlGaN, and has a thickness of 5 angstroms to 800 angstroms.

[0094] The upper confinement layer 106 is any one or any combination of AlGaN, AlN, GaN, AlInN, and AlInGaN, preferably an AlGaN / AlGaN combination, and has a thickness of 500 angstroms to 9000 angstroms.

[0095] The lower confinement layer 101 is any one or any combination of AlGaN, GaN, AlN, InGaN, AlInGaN, and AlInN, preferably an AlGaN / AlGaN combination, and has a thickness of 5000 angstroms to 50000 angstroms.

[0096] The table below compares the performance of the gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer proposed in this embodiment with that of a conventional laser, mainly through comparisons of aging lifetime, optical power, slope efficiency, and temperature quenching ratio:

[0097] Conventional Laser | Laser Variation Aging Lifetime H (65°C@3A) | 19000 | 29000 | 53% | Optical Power (W) | 5.6 | 7.2 | 29% | Slope Efficiency (W / A) | 1.87 | 2.54 | 36% | Temperature Quenching Ratio (PPM) | 269 | 65% surface

[0098] As can be seen from the table above, the gallium nitride-based semiconductor laser with a gradient hole mobility waveguide layer proposed in this embodiment improves the aging lifetime, optical power, and slope efficiency compared to traditional lasers, and reduces the temperature quenching ratio, showing significantly better performance than traditional lasers.

[0099] 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 graded hole mobility waveguide 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, and an upper confinement layer, characterized in that, The upper waveguide layer is a graded hole mobility upper waveguide layer, and the lower waveguide layer is a graded hole mobility lower waveguide layer. The fitting curves of the SIMS test of the In ion intensity distribution or In atom concentration distribution, the fitting curve of the valence band effective state density distribution, and the fitting curve of the hole mobility distribution of the graded hole mobility upper waveguide layer all satisfy any one of the function distributions of ExpGrow1, ExpGrow2, Lorentz, and Bradley. The fitting curves of the SIMS test of the In ion intensity distribution or In atom concentration distribution, the fitting curve of the valence band effective state density distribution, and the fitting curve of the hole mobility distribution of the graded hole mobility lower waveguide layer all satisfy any one of the function distributions of ExpGrow1, ExpGrow2, Lorentz, and Bradley.

2. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer with graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y1=B+A*exp((x1-C) / D), where B is the baseline or asymptotic value, A is the magnitude of the exponential term, C is the characteristic position parameter, D is the characteristic rate parameter, y1 is the SIMS test In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 is the thickness of the waveguide layer with graded hole mobility. The degree, where: -2E26≤B≤0, 7E15≤A≤7E26, ​​-150≤C≤150, 0.002≤D≤200; when the fitting curve of the SIMS test of the In ion intensity distribution or In atom concentration distribution of the waveguide layer with the graded hole mobility satisfies the ExpGrow2 function distribution, the ExpGrow2 function is y2=E+F1*exp((x1-G1) / H1)+F2*exp((x1-G2 / H2), where E is the baseline or asymptotic value, F1 is the amplitude of branch 1, G1 is the characteristic position of branch 1, H1 is the rate parameter of branch 1, F1 is the amplitude of branch 2, G1 is the characteristic position of branch 2, and H1 is the characteristic position of branch 2. The rate parameter y2 represents the SIMS measured In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 represents the thickness of the waveguide layer with graded hole mobility, where: -2E26≤E≤0, 5E15≤F1≤5E26, 5E15≤F2≤5E26, -60≤G1≤60, -60≤G2≤60, 0.002≤H1≤200, 0.002≤H2≤200; the SIMS measured In ion intensity distribution of the waveguide layer with graded hole mobility... When the fitted curve of the In atom concentration distribution satisfies the Lorentz function distribution, the Lorentz function is y3=J+(2*K / π)*(L / (4*(x1-M)^2+L^2)), where J is the baseline background value, K is the integral intensity of the peak term, L is the full width at half maximum (FWHM), M is the peak position, y3 is the SIMS measured In ion intensity or In atom concentration of the waveguide layer with graded hole mobility, and x1 is the thickness of the waveguide layer with graded hole mobility, where -2E26≤J≤0. 6E15≤K≤6E26, 0.006≤L≤60, 0.006≤M≤60; When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer with the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y4=N*ln(-P*ln(x1)), where N is the scaling factor, P is the threshold parameter, y4 is the SIMS test In ion intensity or In atom concentration of the waveguide layer with the graded hole mobility, and x1 is the thickness of the waveguide layer with the graded hole mobility, where: -5E25≤N≤0, 0.009≤P≤900.

3. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitting curve of the SIMS test In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y5=Q+R*exp((x2-S) / T), where Q is the baseline or asymptotic value, R is the magnitude of the exponential term, S is the characteristic position parameter, T is the characteristic velocity parameter, y5 is the SIMS test In ion intensity or In atom concentration of the waveguide layer under the graded hole mobility, and x2 is the thickness of the waveguide layer under the graded hole mobility. Where: 4E15≤Q≤4E30, -2E30≤R≤0, -500000≤S≤0, 200≤T≤200000; when the fitting curve of the SIMS test of the In ion intensity distribution or In atom concentration distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow2 function distribution, the ExpGrow2 function is y6=U+V1*exp((x2-W1) / Z1)+V2*exp((x2-W2 / Z2), U is the baseline or asymptotic value, V1 is the amplitude of branch 1, W1 is the characteristic position of branch 1, Z1 is the rate parameter of branch 1, V2 is the amplitude of branch 2, W2 is the characteristic position of branch 2, and Z2 is the amplitude of branch 2. The rate parameter y6 represents the SIMS measured In ion intensity or In atom concentration of the waveguide layer under graded hole mobility, and x2 represents the waveguide layer thickness under graded hole mobility, where: 5E15≤U≤4E31, -1E30≤V1≤0, -1E30≤V2≤0, -100000≤W1≤100, -100000≤W2≤100, 20≤Z1≤20000, 20≤Z2≤20000; when the fitted curve of the SIMS measured In ion intensity distribution or In atom concentration distribution of the waveguide layer under graded hole mobility satisfies the Lorentz function distribution, the Lorentz function is y7=b+(2*a / π)*(c / (4*(x2-d)^2+c^2)), where b is the baseline background value, a is the peak term integral intensity, c is the half-width at half-maximum (FWHM), and d is the peak position. y7 represents the SIMS measured In ion intensity or In atom concentration of the waveguide layer under graded hole mobility, and x2 represents the waveguide layer thickness under graded hole mobility, where: -2E26≤b≤0, 6E15≤a≤6E26, 0.002≤c≤20, 0.0001≤d≤10; when the fitting curve of the SIMS measured In ion intensity distribution or In atom concentration distribution of the waveguide layer under graded hole mobility satisfies the Bradley function distribution, the Bradley function is y8=f*ln(-g*ln(x2)), where f is the scaling factor, g is the threshold parameter, y8 represents the SIMS measured In ion intensity or In atom concentration of the waveguide layer under graded hole mobility, and x2 represents the waveguide layer thickness under graded hole mobility, where: 3E15≤f≤3E25, 0.05≤g≤500.

4. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitting curve of the valence band effective density of states distribution of the waveguide layer with the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y9=h+i*exp((x1-j) / k), where h is the baseline or asymptotic value, i is the magnitude of the exponential term, j is the characteristic position parameter, k is the characteristic velocity parameter, y9 is the valence band effective density of states of the waveguide layer with the graded hole mobility, and x1 is the thickness of the waveguide layer with the graded hole mobility, where: 3E14≤h≤3E25, 3E13≤i≤3E23, -100≤j≤0, 0.001≤k≤100; when the fitting curve of the valence band effective density of states distribution of the waveguide layer with the graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 10 =m*ln(-n*ln(x1)), where m is the scaling factor, n is the threshold parameter, and y 10 Let x1 be the effective density of states in the valence band of the waveguide layer with graded hole mobility, and let x1 be the thickness of the waveguide layer with graded hole mobility, where: -2E25≤m≤0, 4E-15≤n≤4E-5.

5. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitted curve of the valence band effective density of states distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 11 =p+q*exp((x2-r) / s), where p is the baseline or asymptotic value, q is the magnitude of the exponential term, r is the characteristic location parameter, s is the characteristic rate parameter, and y 11 Let be the valence band effective density of states of the waveguide layer under graded hole mobility, and x2 be the thickness of the waveguide layer under graded hole mobility, where: 2E16≤p≤2E30, -6E30≤q≤0, -30000≤r≤0, 20≤s≤20000; when the fitted curve of the valence band effective density of states distribution of the waveguide layer under graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 12 =t*ln(-u*ln(x2)), where t is the scaling factor, u is the threshold parameter, and y 12 x1 represents the effective density of states in the valence band of the waveguide layer under graded hole mobility, and x2 represents the thickness of the waveguide layer under graded hole mobility, where: 1E13≤t≤1E25, 6E10≤t≤6E20.

6. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitted curve of the hole mobility distribution of the waveguide layer with the gradient hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 13 =v+w*exp((x1-z) / o), where v is the baseline or asymptotic value, w is the magnitude of the exponential term, z is the characteristic position parameter, o is the characteristic rate parameter, and y is the characteristic velocity parameter. 13 Let be the valence band effective density of states of the graded-homogeneous hole mobility waveguide layer, and x1 be the thickness of the graded-homogeneous hole mobility waveguide layer, where: -70000≤v≤0, 20≤w≤20000, -1000≤z≤1000, 0.001≤o≤100; when the fitted curve of the hole mobility distribution of the graded-homogeneous hole mobility waveguide layer satisfies the Bradley function distribution, the Bradley function is y 14 =F3*ln(-G3*ln(x1)), where F3 is the scaling factor, G3 is the threshold parameter, and y 14 Let F be the effective density of states in the valence band of the waveguide layer with graded hole mobility, and let x1 be the thickness of the waveguide layer with graded hole mobility, where: -20000≤F3≤200, 0.0008≤G3≤800.

7. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, When the fitted curve of the valence band effective density of states distribution of the waveguide layer under the graded hole mobility satisfies the ExpGrow1 function distribution, the ExpGrow1 function is y 15 =H3+J3*exp((x2-K3) / L3), where H3 is the baseline or asymptotic value, J3 is the magnitude of the exponential term, K3 is the characteristic position parameter, L3 is the characteristic rate parameter, and y 15 Let x1 be the valence band effective density of states of the waveguide layer under graded hole mobility, and x2 be the thickness of the waveguide layer under graded hole mobility, where: 1E2≤H3≤1E12, -500000000≤J3≤0, -20000≤K3≤200, 20≤L3≤200000; when the fitted curve of the valence band effective density of states distribution of the waveguide layer under graded hole mobility satisfies the Bradley function distribution, the Bradley function is y 16 =M3*ln(-P3*ln(x2)), where M3 is the scaling factor, P3 is the threshold parameter, and y 16 denoted as M3, where M3 represents the effective density of states in the valence band of the waveguide layer under graded hole mobility, and x2 represents the thickness of the waveguide layer under graded hole mobility, where: 10 ≤ M3 ≤ 10000, 0.007 ≤ P3 ≤ 7000.

8. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, The substrate is a GaN single crystal substrate.

9. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, The lower waveguide layer is any one or any combination of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN, with a thickness of 300 Å to 8000 Å; the active layer is an InGaN / GaN quantum well; the upper waveguide layer is any one or any combination of InGaN, GaN / InGaN, GaN / InGaN / GaN, InGaN / GaN, or GaN, with a thickness of 300 Å to 8000 Å.

10. The gallium nitride-based semiconductor laser with a graded hole mobility waveguide layer according to claim 1, characterized in that, The electron blocking layer is any one or any combination of AlGaN, GaN, InGaN, AlInGaN, and AlN, with a thickness of 5 Å to 800 Å; the upper confinement layer is any one or any combination of AlGaN, AlN, GaN, AlInN, and AlInGaN, with a thickness of 500 Å to 9000 Å; the lower confinement layer is any one or any combination of AlGaN, GaN, AlN, InGaN, AlInGaN, and AlInN, with a thickness of 5000 Å to 50000 Å.

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