A semiconductor laser chip with a light absorption loss suppression layer

Abstract

The utility model relates to a semiconductor laser chip with a light absorption loss suppression layer, which includes a substrate, a lower cladding layer, a lower wave layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper cladding layer from bottom to top, and is characterized in that a light absorption loss suppression layer is provided between the electron blocking layer and the upper cladding layer. The refractive index distribution, lattice constant distribution, bandgap width distribution, dielectric constant distribution, piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, bulk elastic modulus distribution, elastic coefficient distribution, etc. of the light absorption loss suppression layer are made to have special curve distributions, so as to achieve the advantages of improving the stimulated radiation quantum efficiency and lasing gain of the laser.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor photoelectric devices, in particular to a semiconductor laser chip with a light absorption loss suppression layer. Background Art

[0002] Lasers are widely used in laser display, laser TV, laser projector, communication, medical treatment, weapons, guidance, ranging, spectral analysis, cutting, precision welding, high-density optical storage and other fields. There are many types of lasers, and the classification methods are also diverse, mainly including solid, gas, liquid, semiconductor and dye types of lasers; compared with other types of lasers, all-solid-state semiconductor lasers have the advantages of small size, high efficiency, light weight, good stability, long life, simple and compact structure, and miniaturization. There are major differences between lasers and nitride semiconductor light-emitting diodes: 1) Lasers are generated by stimulated radiation of carriers, the spectral half-width is small, the brightness is very high, and the output power of a single laser can be in the W level, while nitride semiconductor light-emitting diodes are spontaneous radiation, and the output power of a single light-emitting diode is in the mW level; 2) The current density of the laser is up to KA / cm 2 , which is more than 2 orders of magnitude higher than that of nitride light-emitting diodes, resulting in stronger electron leakage, more serious Auger recombination, stronger polarization effect, more serious electron-hole mismatch, and more serious efficiency attenuation Droop effect; 3) Light-emitting diodes spontaneously radiate incoherent light from high energy levels to low energy levels without external effects, while lasers radiate stimulated transitions. The energy of induced photons should be equal to the difference in energy levels of electron transitions, generating photons and induced photons that are completely coherent light; 4) Different principles: light-emitting diodes produce radiation recombination and luminescence under the action of external voltage when electron holes transition to quantum wells or pn junctions, while lasers require lasing conditions to be met before they can be lased. The carrier inversion distribution in the active region must be met. The stimulated radiation light oscillates back and forth in the resonant cavity, and the propagation in the gain medium amplifies the light. The threshold condition is met so that the gain is greater than the loss, and finally the laser is output.

[0003] Nitride semiconductor lasers have the following problems: the internal optical absorption loss of the laser includes impurity absorption loss, carrier absorption loss, waveguide structure side wall scattering loss and quantum well absorption loss; the optical waveguide impurity absorption loss is high, the inherent carbon impurities in the p-type semiconductor will compensate the acceptor and destroy the p-type, the p-type doping ionization rate is low (less than 10%), and a large amount of unionized Mg acceptor impurities (more than 90%) will produce a self-compensation effect and cause the internal optical loss to increase, resulting in a decrease in the slope efficiency of the laser and an increase in the threshold current; the lattice mismatch and large strain between the epitaxial layers induce a strong piezoelectric polarization effect, resulting in a strong QCSE quantum confined Stark effect, causing energy band tilting, increasing the step difference of the laser valence band, inhibiting hole injection, making it more difficult for holes to transport in the quantum well, uneven carrier injection, and reducing the probability of electron-hole wave function overlap, thereby causing uneven laser gain and reduced radiation recombination efficiency, limiting the improvement of the laser electro-lasing gain. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a semiconductor laser chip with a light absorption loss suppression layer, which includes, from bottom to top, a substrate, a lower cladding layer, a lower wave layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper cladding layer, and is characterized in that a light absorption loss suppression layer is provided between the electron blocking layer and the upper cladding layer.

[0005] Specifically, the refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer have any one of a wave-type distribution, a fluctuating distribution, or an irregular oscillation distribution.

[0006] Specifically, the refractive index distribution of the optical absorption loss suppression layer has a curve distribution of function y=A1sin(B1x+C1), the lattice constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=D1sin(E1x+F1), the dielectric constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=G1sin(H1x+I1), and the bandgap width distribution of the optical absorption loss suppression layer has a curve distribution of function y=J1cos(K1x+L1); or the refractive index distribution of the optical absorption loss suppression layer has a curve distribution of function y=A2cos(B2x+C2), the lattice constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=D2cos(E2x+F2), the dielectric constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=G2cos(H2x+I2), and the bandgap width distribution of the optical absorption loss suppression layer has a curve distribution of function y=J2sin(K2x+L2).

[0007] Specifically, the refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer have the following relationship: D1≤G1≤A1≤J1 and D2≤G2≤A2≤J2.

[0008] Through the above technical means, the acceptor compensation and p-type destruction of inherent carbon impurities are reduced, the ionization rate of Mg doping is increased, the light absorption loss of the self-compensation effect of un-ionized host impurities is suppressed, the slope efficiency of the laser is improved, and the threshold current of the laser is reduced.

[0009] Specifically, the piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, bulk elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have any one of wave-type distribution, wavy distribution, or irregular oscillation distribution.

[0010] Specifically, the piezoelectric polarization coefficient of the light absorption loss suppression layer has a curve distribution of function y=M1cos(N1x+O1), the spontaneous polarization coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=P1sin(Q1x+R1), the volume elastic modulus distribution of the light absorption loss suppression layer has a curve distribution of function y=S1sin(T1x+U1), and the elastic coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=V1sin(W1x+Z1); or the piezoelectric polarization coefficient of the light absorption loss suppression layer has a curve distribution of function y=M2sin(N2x+O2), the spontaneous polarization coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=P2cos(Q2x+R2), the volume elastic modulus distribution of the light absorption loss suppression layer has a curve distribution of function y=S2cos(T2x+U2), and the elastic coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=V2cos(W2x+Z2).

[0011] Specifically, the piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, bulk elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have the following relationship: S1≤V1≤M1≤P1 and S2≤V2≤M2≤P2.

[0012] Through the above-mentioned technical means, the lattice mismatch and strain between the electron blocking layer and the upper cladding layer can be alleviated, the hole injection band order of the electron blocking layer can be reduced, the hole injection efficiency and injection uniformity can be improved, and the stimulated radiation quantum efficiency and lasing gain of the laser can be improved.

[0013] Specifically, the refractive index distribution, lattice constant distribution, bandgap width distribution, dielectric constant distribution, piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have the following relationships: S1≤D1≤G1≤V1≤A1≤J1≤M1≤P1 and S2≤D2≤G2≤V2≤A2≤J2≤M2≤P2; the Al element distribution of the light absorption loss suppression layer has a function y=mcos(nx+p) curve distribution; the Al / O element ratio distribution of the light absorption loss suppression layer has a function y=mcos(nx+p) curve distribution.

[0014] Specifically, the active layer is a periodic structure composed of a well layer and a barrier layer, and the number of periods is 3≥m≥1. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the utility model. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. Other features, objects and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings:

[0016] Figure 1 It is a schematic structural diagram of a semiconductor laser chip with a light absorption loss suppression layer according to an embodiment of the utility model;

[0017] Figure 2 It is a SIMS secondary ion mass spectrum of a semiconductor laser chip with a light absorption loss suppression layer according to an embodiment of the utility model;

[0018] Figure 3 This is a SIMS secondary ion mass spectrum (partially enlarged view) of a semiconductor laser chip with a light absorption loss suppression layer according to an embodiment of the utility model;

[0019] Figure 4-8 This is a TEM transmission electron microscope image of a semiconductor laser chip with a light absorption loss suppression layer according to an embodiment of the utility model;

[0020] Fig. 9 This is a SIMS secondary ion mass spectrum (partially enlarged view) of a semiconductor laser chip with a light absorption loss suppression layer according to an embodiment of the utility model.

[0021] The meaning of the numbers in the figure are: 100, substrate; 101, lower cladding layer; 102, lower waveguide layer; 103, active layer; 104, upper waveguide layer; 105, electron blocking layer; 106, upper cladding layer; 107, light absorption loss suppression layer. DETAILED DESCRIPTION

[0022] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant utility model, rather than to limit the utility model. It is also necessary to explain that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings.

[0023] like Figure 1 As shown, the present application proposes a semiconductor laser chip with a light absorption loss suppression layer, which includes, from bottom to top, a substrate 100, a lower cladding layer 101, a lower wave layer, an active layer 103, an upper waveguide layer 104, an electron blocking layer 105, and an upper cladding layer 106, with a light absorption loss suppression layer 107 between the electron blocking layer 105 and the upper cladding layer 106.

[0024] In order to reduce the acceptor compensation and p-type destruction of inherent carbon impurities, increase the ionization rate of Mg doping, suppress the light absorption loss of the self-compensation effect of un-ionized host impurities, improve the slope efficiency of the laser, and reduce the threshold current of the laser, the refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer 107 are specially adjusted so that the above distributions have any one of wavy distribution, fluctuating distribution, or irregular oscillation distribution.

[0025] Specifically, the refractive index distribution of the light absorption loss suppression layer 107 has a function y=A1sin(B1x+C1) curve distribution or a function y=A2cos(B2x+C2) curve distribution;

[0026] At the same time, the above technical solutions can achieve the following effects:

[0027]

[0028] Specifically, the lattice constant distribution of the light absorption loss suppression layer 107 has a function y=D1sin(E1x+F1) curve distribution or a function y=D2cos(E2x+F2) curve distribution;

[0029] At the same time, the above technical solutions can achieve the following effects:

[0030]

[0031] Specifically, the dielectric constant distribution of the light absorption loss suppression layer 107 has a function y=G1sin(H1x+I1) curve distribution or a function y=G2cos(H2x+I2) curve distribution;

[0032] At the same time, the above technical solutions can achieve the following effects:

[0033]

[0034]

[0035] Specifically, the bandgap width distribution of the light absorption loss suppression layer 107 has a function y=J1cos(K1x+L1) curve distribution or a function y=J2sin(K2x+L2) curve distribution;

[0036] At the same time, the above technical solutions can achieve the following effects:

[0037]

[0038] In the first specific embodiment, the refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer 107 can be adjusted simultaneously so that when it satisfies the above-mentioned curve distribution, it also satisfies D1≤G1≤A1≤J1 or D2≤G2≤A2≤J2, thereby better achieving the technical effect.

[0039] In order to alleviate the lattice mismatch and strain between the electron blocking layer and the upper cladding layer, reduce the hole injection band order of the electron blocking layer, improve the hole injection efficiency and injection uniformity, and improve the stimulated radiation quantum efficiency and lasing gain of the laser; the present application makes special adjustments to the piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer 107, so that the above distribution has any one of a wavy distribution, a fluctuating distribution, or an irregular oscillation distribution.

[0040] Specifically, the piezoelectric polarization coefficient of the light absorption loss suppression layer 107 has a function y=M1cos(N1x+O1) curve distribution or a function y=M2sin(N2x+O2) curve distribution;

[0041] At the same time, the above technical solutions can achieve the following effects:

[0042]

[0043]

[0044] Specifically, the spontaneous polarization coefficient distribution of the light absorption loss suppression layer 107 has a function y=P1sin(Q1x+R1) curve distribution or a function y=P2cos(Q2x+R2) curve distribution;

[0045] At the same time, the above technical solutions can achieve the following effects:

[0046]

[0047] Specifically, the volume elastic modulus distribution of the light absorption loss suppression layer 107 has a function y=S1sin(T1x+U1) curve distribution or a function y=S2cos(T2x+U2) curve distribution;

[0048] At the same time, the above technical solutions can achieve the following effects:

[0049]

[0050] Specifically, the elastic coefficient distribution of the light absorption loss suppression layer 107 has a function y=V1sin(W1x+Z1) curve distribution or a function y=V2cos(W2x+Z2) curve distribution;

[0051] At the same time, the above technical solutions can achieve the following effects:

[0052]

[0053] In the second specific embodiment, the piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer 107 can be adjusted simultaneously so that when they satisfy the above-mentioned curve distribution, they also satisfy S1≤V1≤M1≤P1 or S2≤V2≤M2≤P2, thereby better achieving the technical effect.

[0054] In the third specific embodiment, in order to simultaneously achieve the effects of the first specific embodiment and the second specific embodiment, the refractive index distribution, lattice constant distribution, bandgap width distribution, dielectric constant distribution, piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer 107 can be adjusted simultaneously so that the above distributions have the following relationship: S1≤D1≤G1≤V1≤A1≤J1≤M1≤P1 or S2≤D2≤G2≤V2≤A2≤J2≤M2≤P2.

[0055] Specifically, the Al element distribution of the light absorption loss suppression layer 107 has a function y=mcos(nx+p) curve distribution; the Al / O element ratio distribution of the light absorption loss suppression layer 107 has a function y=mcos(nx+p) curve distribution.

[0056] At the same time, the above technical solutions can achieve the following effects:

[0057]

[0058] In a specific embodiment, Figure 2 and Figure 3As shown, the Al element concentration of the graded polarization layer 107 gradually increases from the upper cladding layer 106 to the electron blocking layer 105, and the rising curve has a function y=mcos(nx+p) curve distribution; Fig. 9 The O element concentration of the variable polarization layer 107 shown in the figure remains basically unchanged from the upper cladding layer 106 to the electron blocking layer 105, so the Al / O element ratio distribution of the light absorption loss suppression layer 107 in this embodiment has a function y=mcos(nx+p) curve distribution.

[0059] The above technical solution can achieve the following effects:

[0060]

[0061] Specifically, in order to better regulate the piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, Philips ionization degree distribution, elastic coefficient distribution, covalent bond energy distribution, polarization optical phonon energy distribution, transverse sound velocity distribution, and saturated electron drift rate distribution of the gradient polarization layer 107 to have the above-mentioned curve distribution, the gradient polarization layer 107 is usually any one or any combination of AlGaN, GaN, AlInN, AlInGaN, InGaN / GaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, AlGaN / AlGaN superlattice, AlGaN / GaN superlattice, AlGaN / AlInGaN superlattice, and AlGaN / AlInN superlattice, and the thickness of the gradient polarization layer 107 is 30 to 30,000 angstroms.

[0062] The active layer 103 is a periodic structure composed of a well layer and a barrier layer, the number of periods is 3 ≥ m ≥ 1, and the well layer is any one or any of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN, and diamond. combination, with a thickness of 10 to 150 angstroms, and the barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN, and diamond, with a thickness of 10 to 200 angstroms. The lower cladding layer 101, the lower waveguide layer 102, the upper waveguide layer 104, the electron blocking layer 105, and the upper cladding layer 106 are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN, and diamond. The substrate 100 includes any one of sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, sapphire / SiNx, sapphire / SiO2 / SiNx composite substrate, sapphire / SiNx / SiO2 composite substrate, magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrates.

[0063] like Figure 4 As shown, the thickness of the upper cladding layer 106 in this embodiment is 2827 angstroms.

[0064] like Figure 5 As shown, in this embodiment, the electron blocking layer 105 is composed of multiple components, and the thicknesses of different components include: 16 angstroms, 19 angstroms, 21 angstroms, 23 angstroms, 25 angstroms, 31 angstroms, 36 angstroms and 37 angstroms, and there is also a transition region with a thickness of 116 angstroms in the transition region from the electron blocking layer 105 to the upper waveguide layer 104, and the composition of this region is different from that of other regions.

[0065] like Figure 6 As shown, in this embodiment, the thickness of the upper waveguide layer 104 is 2471 angstroms.

[0066] like Figure 7 As shown, by observing the TEM image at a scale of 10 nm, it can be seen that the active layer is a periodic structure composed of a well layer and a barrier layer, and the number of periods is between 1 and 3. Further observation of the thickness of the barrier layer and the well layer shows that in this embodiment, the thickness range of the barrier layer and the well layer is 15 to 96 angstroms.

[0067] like Figure 8 As shown, in this embodiment, the thickness of the lower waveguide layer 102 is 5387 angstroms.

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

Claims

1. A semiconductor laser chip with a light absorption loss suppression layer, comprising, from bottom to top, a substrate, a lower cladding layer, a lower wave layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper cladding layer, characterized in that: A light absorption loss suppression layer is provided between the electron blocking layer and the upper cladding layer.

2. A semiconductor laser chip having a light absorption loss suppression layer as claimed in claim 1, characterized in that: The refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer have any one of wave-type distribution, fluctuating distribution, or irregular oscillation distribution.

3. A semiconductor laser chip having a light absorption loss suppression layer as claimed in claim 2, characterized in that: The refractive index distribution of the optical absorption loss suppression layer has a curve distribution of function y=A1sin(B1x+C1), the lattice constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=D1sin(E1x+F1), the dielectric constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=G1sin(H1x+I1), and the bandgap width distribution of the optical absorption loss suppression layer has a curve distribution of function y=J1cos(K1x+L1); or the refractive index distribution of the optical absorption loss suppression layer has a curve distribution of function y=A2cos(B2x+C2), the lattice constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=D2cos(E2x+F2), the dielectric constant distribution of the optical absorption loss suppression layer has a curve distribution of function y=G2cos(H2x+I2), and the bandgap width distribution of the optical absorption loss suppression layer has a curve distribution of function y=J2sin(K2x+L2).

4. A semiconductor laser chip having a light absorption loss suppression layer as claimed in claim 3, characterized in that: The refractive index distribution, lattice constant distribution, bandgap width distribution, and dielectric constant distribution of the light absorption loss suppression layer have the following relationship: D1≤G1≤A1≤J1 and D2≤G2≤A2≤J2.

5. The semiconductor laser chip having a light absorption loss suppression layer according to claim 4, characterized in that: The piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, bulk elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have any one of wave-type distribution, fluctuating distribution, or irregular oscillation distribution.

6. The semiconductor laser chip having a light absorption loss suppression layer according to claim 5, characterized in that: The piezoelectric polarization coefficient of the light absorption loss suppression layer has a curve distribution of function y=M1cos(N1x+O1), the spontaneous polarization coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=P1sin(Q1x+R1), the volume elastic modulus distribution of the light absorption loss suppression layer has a curve distribution of function y=S1sin(T1x+U1), and the elastic coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=V1sin(W1x+Z1); or the piezoelectric polarization coefficient of the light absorption loss suppression layer has a curve distribution of function y=M2sin(N2x+O2), the spontaneous polarization coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=P2cos(Q2x+R2), the volume elastic modulus distribution of the light absorption loss suppression layer has a curve distribution of function y=S2cos(T2x+U2), and the elastic coefficient distribution of the light absorption loss suppression layer has a curve distribution of function y=V2cos(W2x+Z2).

7. The semiconductor laser chip having a light absorption loss suppression layer according to claim 6, characterized in that: The piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have the following relationship: S1≤V1≤M1≤P1 and S2≤V2≤M2≤P2.

8. The semiconductor laser chip having a light absorption loss suppression layer according to claim 7, characterized in that: The refractive index distribution, lattice constant distribution, bandgap width distribution, dielectric constant distribution, piezoelectric polarization coefficient distribution, spontaneous polarization coefficient distribution, volume elastic modulus distribution, and elastic coefficient distribution of the light absorption loss suppression layer have the following relationships: S1≤D1≤G1≤V1≤A1≤J1≤M1≤P1 and S2≤D2≤G2≤V2≤A2≤J2≤M2≤P2; the Al element distribution of the light absorption loss suppression layer has a function y=mcos(nx+p) curve distribution; the Al / O element ratio distribution of the light absorption loss suppression layer has a function y=mcos(nx+p) curve distribution.

9. The semiconductor laser chip having a light absorption loss suppression layer according to claim 1, characterized in that: The active layer is a periodic structure composed of a well layer and a barrier layer, and the number of periods is 3≥m≥1.

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