Semiconductor laser with lower waveguide layer for inhibiting optical catastrophe

Abstract

The invention provides a semiconductor laser with a lower waveguide layer for inhibiting optical catastrophe. The semiconductor laser comprises a substrate, a lower coating layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper coating layer which are sequentially arranged from bottom to top. By designing the volume elastic modulus and the change angle of the deformation potential of the lower waveguide layer, the stress distribution uniformity and thermal expansion distribution uniformity between the lower waveguide layer and the lower coating layer interface, between the lower waveguide layer and the active layer interface and between the lower waveguide layer interfaces are improved, and the optical catastrophe of the laser is reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor optoelectronic devices, and in particular to a semiconductor laser having a lower waveguide layer for suppressing optical catastrophe. Background Art

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

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

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

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

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

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

[0008] Nitride semiconductor lasers have the following problems: the resistance of the epitaxial and chip materials will produce Joule heat loss and carrier absorption loss under current injection, making the temperature distribution of the laser uneven, causing uneven distribution of thermal expansion and thermal stress, and causing optical catastrophic damage, temperature quenching, laser breakage and other problems. Summary of the invention

[0009] To solve one of the above technical problems, the present invention provides a semiconductor laser having a lower waveguide layer for suppressing optical catastrophe.

[0010] An embodiment of the present invention provides a semiconductor laser having an optical catastrophe suppressed lower waveguide layer, comprising a substrate, a lower cladding layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper cladding layer arranged in sequence from bottom to top, wherein the lower waveguide layer comprises a first optical catastrophe suppressed lower waveguide layer, a second optical catastrophe suppressed lower waveguide layer and a third optical catastrophe suppressed lower waveguide layer arranged in sequence from bottom to top, wherein an interface between the first optical catastrophe suppressed lower waveguide layer and the lower cladding layer, an interface between the second optical catastrophe suppressed lower waveguide layer and the first optical catastrophe suppressed lower waveguide layer, and an interface between the third optical catastrophe suppressed lower waveguide layer and the second optical catastrophe suppressed lower waveguide layer all have bulk elastic modulus distribution characteristics and deformation potential distribution characteristics;

[0011] The rising angle of the valley position of the bulk elastic modulus of the first optical catastrophe suppression waveguide layer toward the lower cladding layer is α, the falling angle of the peak position of the bulk elastic modulus of the second optical catastrophe suppression waveguide layer toward the lower cladding layer is β, and the rising angle of the valley position of the bulk elastic modulus of the third optical catastrophe suppression waveguide layer toward the lower cladding layer is γ, wherein: 45°≤γ≤β≤α≤90°;

[0012] The rising angle of the valley position of the deformation potential of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is θ, the falling angle of the peak position of the deformation potential of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is δ, and the rising angle of the valley position of the deformation potential of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is σ, wherein: 40°≤σ≤δ≤θ≤90°.

[0013] Preferably, the interface between the first optical catastrophe suppression lower waveguide layer and the lower cladding layer, the interface between the second optical catastrophe suppression lower waveguide layer and the first optical catastrophe suppression lower waveguide layer, and the interface between the third optical catastrophe suppression lower waveguide layer and the second optical catastrophe suppression lower waveguide layer also have separation energy distribution characteristics and heavy hole effective mass distribution characteristics;

[0014] The rising angle of the valley position of the separation energy of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is The descending angle of the peak position of the separation energy of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is ψ, and the rising angle of the valley position of the separation energy of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is μ, wherein:

[0015] The rising angle of the valley position of the heavy hole effective mass of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is υ, the descending angle of the peak position of the heavy hole effective mass of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is ρ, and the rising angle of the valley position of the heavy hole effective mass of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is ω, wherein: 30°≤ω≤ρ≤υ≤90°.

[0016] Preferably, the relationship between the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass in the first optical catastrophe suppression waveguide layer toward the lower cladding layer, the bulk elastic modulus, deformation potential, separation energy, and falling angle of the peak position of the heavy hole effective mass in the second optical catastrophe suppression waveguide layer toward the lower cladding layer, and the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass in the third optical catastrophe suppression waveguide layer toward the lower cladding layer is:

[0017] Preferably, the bulk elastic modulus of the interface between the first optical catastrophe-suppressing lower waveguide layer and the lower cladding layer has a function y1=D+lnx1+C*e x1 Curve distribution;

[0018] The deformation potential of the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y2=E+F*e x1 lnx1 curve distribution;

[0019] The separation energy of the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y3=G+H*e x1 lnx1 curve distribution;

[0020] The effective mass of heavy holes at the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y4=J+K*e x1 +x1 curve distribution;

[0021] Wherein: J≤E≤G≤D, x1 is the depth of the first optical catastrophe suppression lower waveguide layer toward the second optical catastrophe suppression lower waveguide layer.

[0022] Preferably, the bulk elastic modulus of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y5=L+M*e x2 / lnx2 fourth quadrant curve distribution;

[0023] The deformation potential of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y6=N+M*e x2 / lnx2 fourth quadrant curve distribution;

[0024] The separation energy of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y7=P+Q*e x2 / lnx2 fourth quadrant curve distribution;

[0025] The effective mass of heavy holes at the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y8=R+x2 2 -T*e x2 The third quadrant curve distribution;

[0026] Wherein: R≤N≤P≤L, x2 is the depth of the second optical catastrophe suppression lower waveguide layer toward the third optical catastrophe suppression lower waveguide layer.

[0027] Preferably, the bulk elastic modulus of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y9=U+V*(e x3 -e -x3 )Limiting curve distribution;

[0028] The deformation potential of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y 10 =W+x3 -A The second quadrant curve distribution, A is an even number and A>1;

[0029] The separation energy of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y 11 =S+x3 -B The second quadrant curve distribution, B is an even number and B>1;

[0030] The heavy hole effective mass at the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y2=Z+x3lnx3 limited curve distribution;

[0031] Wherein: Z≤W≤S≤U, x3 is the depth of the waveguide layer toward the active layer under the third optical catastrophe suppression.

[0032] Preferably, the lower waveguide layer is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5nm to 1000nm.

[0033] Preferably, the active layer is a periodic structure composed of a well layer and a barrier layer, and the well layer of the active 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, and the thickness is 100 nm. The thickness of the active layer is 10 angstroms to 150 angstroms, and the barrier layer of the active 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, and the thickness is 10 angstroms to 200 angstroms.

[0034] Preferably, the upper waveguide layer is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5nm to 1000nm.

[0035] Preferably, the lower cladding layer, electron blocking layer and upper cladding layer are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN and diamond.

[0036] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, graphene, sapphire / SiN x , Sapphire / SiO2 / SiN x Composite substrate, sapphire / SiN x Any one of a / SiO2 composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0037] The beneficial effects of the present invention are as follows: the semiconductor laser with a lower waveguide layer for suppressing optical catastrophe proposed by the present invention improves the uniformity of stress distribution and thermal expansion distribution at the interface between the lower waveguide layer and the lower cladding layer, the interface between the lower waveguide layer and the active layer, and the interfaces between the layers of the lower waveguide layer by designing the change angle of the volume elastic modulus and the deformation potential of the lower waveguide layer, thereby reducing the optical catastrophe of the laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0039] Figure 1 A schematic diagram of the structure of a semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention;

[0040] Figure 2 This is a structural SIMS secondary ion mass spectrum of a semiconductor laser with a lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention;

[0041] Figure 3 It is a partial enlarged view of the SIMS secondary ion mass spectrum of the structure of the semiconductor laser with the lower waveguide layer for suppressing optical catastrophe according to the embodiment of the present invention;

[0042] Figure 4 This is a TEM lens electron microscope image of a semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention;

[0043] Figure 5 This is a TEM lens electron microscope image of the electron blocking layer of the semiconductor laser with the lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention;

[0044] Figure 6 This is a TEM lens electron microscope image of the upper waveguide layer of the semiconductor laser having a lower waveguide layer that suppresses optical catastrophe according to an embodiment of the present invention;

[0045] Figure 7 This is a TEM lens electron microscope image of the active layer of the semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention;

[0046] Figure 8 This is a TEM lens electron microscope image of the lower waveguide layer of the semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to an embodiment of the present invention.

[0047] Reference numerals:

[0048] 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;

[0049] 102a, a first waveguide layer for suppressing optical catastrophe, 102b, a second waveguide layer for suppressing optical catastrophe, 102c, a third waveguide layer for suppressing optical catastrophe. DETAILED DESCRIPTION

[0050] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0051] like Figures 1 to 8 As shown, this embodiment provides a semiconductor laser with a lower waveguide layer for suppressing optical catastrophe, including a substrate 100, a lower cladding layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104, an electron blocking layer 105 and an upper cladding layer 106 arranged in sequence from bottom to top.

[0052] Specifically, in this embodiment, the semiconductor laser having a lower waveguide layer for suppressing optical catastrophe is provided with a substrate 100, a lower cladding layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104, an electron blocking layer 105 and an upper cladding layer 106 in order from bottom to top. The lower waveguide layer 102 has a bulk elastic modulus distribution characteristic and a deformation potential distribution characteristic, so that the lower waveguide layer 102 becomes a lower waveguide layer for suppressing optical catastrophe.

[0053] More specifically, in this embodiment, the lower waveguide layer 102 includes a first optical catastrophe suppression lower waveguide layer 102a, a second optical catastrophe suppression lower waveguide layer 102b, and a third optical catastrophe suppression lower waveguide layer 102c, which are sequentially arranged from bottom to top. The interface between the first optical catastrophe suppression lower waveguide layer 102a and the lower cladding layer 101, the interface between the second optical catastrophe suppression lower waveguide layer 102b and the first optical catastrophe suppression lower waveguide layer 102a, and the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b all have bulk elastic modulus distribution characteristics and deformation potential distribution characteristics. At the same time, the bulk elastic modulus and deformation potential in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b, and the third optical catastrophe suppression lower waveguide layer 102c also have a certain change trend toward the lower cladding layer 101, which is specifically manifested as follows:

[0054] The variation trend of the bulk elastic modulus in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b and the third optical catastrophe suppression lower waveguide layer 102c toward the lower cladding layer 101 is:

[0055] The valley position of the bulk elastic modulus of the first optical catastrophe suppression waveguide layer 102a shows an upward trend toward the lower cladding layer 101;

[0056] The peak position of the bulk elastic modulus of the second optical catastrophe suppression waveguide layer 102b shows a downward trend toward the lower cladding layer 101;

[0057] The valley position of the bulk elastic modulus of the third optical catastrophe suppression waveguide layer 102 c shows an upward trend toward the lower cladding layer 101 .

[0058] Furthermore, the rising angle of the valley position of the bulk elastic modulus of the first optical catastrophe suppression waveguide layer 102a toward the lower cladding layer 101 is α, the descending angle of the peak position of the bulk elastic modulus of the second optical catastrophe suppression waveguide layer 102b toward the lower cladding layer 101 is β, and the rising angle of the valley position of the bulk elastic modulus of the third optical catastrophe suppression waveguide layer 102c toward the lower cladding layer 101 is γ, wherein: 45°≤γ≤β≤α≤90°.

[0059] The variation trend of the deformation potential in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b and the third optical catastrophe suppression lower waveguide layer 102c toward the lower cladding layer 101 is:

[0060] The valley position of the deformation potential of the waveguide layer 102a under the first optical catastrophe suppression shows an upward trend toward the lower cladding layer 101;

[0061] The peak position of the deformation potential of the second optical catastrophe suppression waveguide layer 102b shows a downward trend toward the lower cladding layer 101;

[0062] The valley position of the deformation potential of the third optical catastrophe suppression waveguide layer 102 c shows an upward trend toward the lower cladding layer 101 .

[0063] Furthermore, the rising angle of the valley position of the deformation potential of the first optical catastrophe suppression waveguide layer 102a toward the lower cladding layer 101 is θ, the falling angle of the peak position of the second optical catastrophe suppression waveguide layer 102b toward the lower cladding layer 101 is δ, and the rising angle of the valley position of the third optical catastrophe suppression waveguide layer 102c toward the lower cladding layer 101 is σ, wherein: 40°≤σ≤δ≤θ≤90°.

[0064] In this embodiment, by designing the volume elastic modulus and the change angle of the deformation potential of the lower waveguide layer 102, the stress distribution uniformity and the thermal expansion distribution uniformity at the interface between the lower waveguide layer 102 and the lower cladding layer 101, the interface between the lower waveguide layer 102 and the active layer 103, and the interfaces between the layers of the lower waveguide layer 102 are improved, thereby reducing the optical catastrophe of the laser.

[0065] In some optional embodiments, the interface between the first optical catastrophe suppression lower waveguide layer 102a and the lower cladding layer 101, the interface between the second optical catastrophe suppression lower waveguide layer 102b and the first optical catastrophe suppression lower waveguide layer 102a, and the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b also have separation energy distribution characteristics and heavy hole effective mass distribution characteristics. At the same time, the separation energy and heavy hole effective mass in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b and the third optical catastrophe suppression lower waveguide layer 102c also have a certain change trend toward the lower cladding layer 101, which is specifically manifested as follows:

[0066] The variation trend of the separation energy in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b and the third optical catastrophe suppression lower waveguide layer 102c toward the lower cladding layer 101 is:

[0067] The valley position of the separation energy of the first optical catastrophe suppression waveguide layer 102a shows an upward trend toward the lower cladding layer 101;

[0068] The peak position of the separation energy of the second optical catastrophe suppression waveguide layer 102b shows a downward trend toward the lower cladding layer 101;

[0069] The position of the valley value of the separation energy of the third optical catastrophe suppression waveguide layer 102 c shows an upward trend toward the lower cladding layer 101 .

[0070] Furthermore, the rising angle of the valley position of the separation energy of the first optical catastrophe suppression waveguide layer 102a toward the lower cladding layer 101 is The descending angle of the peak position of the separation energy of the waveguide layer 102b under the second optical catastrophe suppression to the lower cladding layer 101 is ψ, and the rising angle of the valley position of the separation energy of the waveguide layer 102c under the third optical catastrophe suppression to the lower cladding layer 101 is μ, wherein:

[0071] The variation trend of the effective mass of heavy holes in the first optical catastrophe suppression lower waveguide layer 102a, the second optical catastrophe suppression lower waveguide layer 102b and the third optical catastrophe suppression lower waveguide layer 102c toward the lower cladding layer 101 is:

[0072] The valley position of the heavy hole effective mass of the first optical catastrophe suppression waveguide layer 102a shows an upward trend toward the lower cladding layer 101;

[0073] The peak position of the heavy hole effective mass of the second optical catastrophe suppression waveguide layer 102b shows a downward trend toward the lower cladding layer 101;

[0074] The valley position of the heavy hole effective mass of the third optical catastrophe suppression waveguide layer 102 c shows an upward trend toward the lower cladding layer 101 .

[0075] Furthermore, the rising angle of the valley position of the heavy hole effective mass of the first waveguide layer 102a for suppressing optical catastrophe toward the lower cladding layer 101 is υ, the descending angle of the peak position of the heavy hole effective mass of the second waveguide layer 102b for suppressing optical catastrophe toward the lower cladding layer 101 is ρ, and the rising angle of the valley position of the third waveguide layer 102c for suppressing optical catastrophe toward the lower cladding layer 101 is ω, wherein: 30°≤ω≤ρ≤υ≤90°.

[0076] Furthermore, the relationship between the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass of the first optical catastrophe suppression waveguide layer 102a toward the lower cladding layer 101, the bulk elastic modulus, deformation potential, separation energy, and falling angle of the peak position of the heavy hole effective mass of the second optical catastrophe suppression waveguide layer 102b toward the lower cladding layer 101, and the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass of the third optical catastrophe suppression waveguide layer 102c toward the lower cladding layer 101 is as follows:

[0077] In this embodiment, the separation energy of the lower waveguide layer 102 and the change angle of the effective mass of heavy holes are designed to reduce the two-dimensional island structure or three-dimensional island structure caused by InN segregation in the lower waveguide layer 102, improve the crystal quality of the lower waveguide layer 102, suppress the thermal degradation and component fluctuation of the lower waveguide layer 102, and further suppress the optical catastrophe of the laser. The optical catastrophe ratio of the laser is reduced from 35PPM to 6PPM.

[0078] In some optional embodiments, the bulk elastic modulus distribution characteristics, deformation potential distribution characteristics, separation energy distribution characteristics and heavy hole effective mass distribution characteristics of the interface between the first optical catastrophe suppression lower waveguide layer 102a and the lower cladding layer 101 are specifically manifested as follows:

[0079] The bulk elastic modulus of the interface between the first optical catastrophe suppression lower waveguide layer 102a and the lower cladding layer 101 has the function y1=D+lnx1+C*e x1 Curve distribution;

[0080] The deformation potential of the interface between the first optical catastrophe-suppressing lower waveguide layer 102a and the lower cladding layer 101 has a function y2=E+F*e x1 lnx1 curve distribution;

[0081] The separation energy of the interface between the first optical catastrophe-suppressing lower waveguide layer 102a and the lower cladding layer 101 has a function y3=G+H*e x1 lnx1 curve distribution;

[0082] The effective mass of heavy holes at the interface between the first optical catastrophe-suppressing lower waveguide layer 102a and the lower cladding layer 101 has a function y4=J+K*e x1 +x1 curve distribution;

[0083] Wherein: J≤E≤G≤D, x1 is the depth of the first optical catastrophe suppression lower waveguide layer 102a toward the second optical catastrophe suppression lower waveguide layer 102b.

[0084] In some optional embodiments, the bulk elastic modulus distribution characteristics, deformation potential distribution characteristics, separation energy distribution characteristics and heavy hole effective mass distribution characteristics of the interface between the second optical catastrophe suppression waveguide layer 102b and the first optical catastrophe suppression waveguide layer 102a are specifically manifested as follows:

[0085] The bulk elastic modulus of the interface between the second optical catastrophe suppression waveguide layer 102b and the first optical catastrophe suppression waveguide layer 102a has a function y5=L+M*e x2 / lnx2 fourth quadrant curve distribution;

[0086] The deformation potential of the interface between the second optical catastrophe suppression waveguide layer 102b and the first optical catastrophe suppression waveguide layer 102a has a function y6=N+M*ex2 / lnx2 fourth quadrant curve distribution;

[0087] The separation energy at the interface between the second optical catastrophe suppression waveguide layer 102b and the first optical catastrophe suppression waveguide layer 102a has a function y7=P+Q*e x2 / lnx2 fourth quadrant curve distribution;

[0088] The effective mass of heavy holes at the interface between the second optical catastrophe suppression lower waveguide layer 102b and the first optical catastrophe suppression lower waveguide layer 102a has a function y8=R+x2 2 -T*e x2 The third quadrant curve distribution;

[0089] Wherein: R≤N≤P≤L, x2 is the depth of the second optical catastrophe suppression lower waveguide layer 102b toward the third optical catastrophe suppression lower waveguide layer 102c.

[0090] In some optional embodiments, the bulk elastic modulus distribution characteristics, deformation potential distribution characteristics, separation energy distribution characteristics and heavy hole effective mass distribution characteristics of the interface between the third optical catastrophe suppression waveguide layer 102c and the second optical catastrophe suppression waveguide layer 102b are specifically manifested as follows:

[0091] The bulk elastic modulus of the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b has a function y9=U+V*(e x3 -e -x3 )Limiting curve distribution;

[0092] The deformation potential of the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b has a function y 10 =W+x3 -A The second quadrant curve distribution, A is an even number and A>1;

[0093] The separation energy of the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b has a function y 11 =S+x3 -B The second quadrant curve distribution, B is an even number and B>1;

[0094] The heavy hole effective mass at the interface between the third optical catastrophe suppression lower waveguide layer 102c and the second optical catastrophe suppression lower waveguide layer 102b has a function y2=Z+x3lnx3 limited curve distribution;

[0095] Wherein: Z≤W≤S≤U, x3 is the depth of the third optical catastrophe suppression lower waveguide layer 102c toward the active layer 103.

[0096] In this embodiment, by designing the interface variation curve of the bulk elastic modulus, deformation potential, separation energy and heavy hole effective mass of the lower waveguide layer 102, the stress distribution uniformity and thermal expansion distribution uniformity between the interface between the lower waveguide layer 102 and the lower cladding layer 101, the interface between the lower waveguide layer 102 and the active layer 103, and the interfaces between the layers of the lower waveguide layer 102 can be further improved, the optical catastrophe of the laser can be reduced, the two-dimensional island structure or the three-dimensional island structure caused by the InN segregation of the lower waveguide layer 102 can be reduced, the crystal quality of the lower waveguide layer 102 can be improved, the thermal degradation and component fluctuation of the lower waveguide layer 102 can be suppressed, and the optical catastrophe of the laser can be further suppressed.

[0097] In some optional embodiments, the lower waveguide layer 102 is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5 nm to 1000 nm.

[0098] In some optional embodiments, the active layer 103 is a periodic structure consisting of a well layer and a barrier layer.

[0099] Specifically, the well layer of the active layer 103 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, and has a thickness of 10 to 150 angstroms.

[0100] The barrier layer of the active layer 103 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, and has a thickness of 10 to 200 angstroms.

[0101] In some optional embodiments, the upper waveguide layer 104 is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5 nm to 1000 nm.

[0102] In some optional embodiments, the lower cladding layer 101, 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.

[0103] In some optional embodiments, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, graphene, sapphire / SiN x , Sapphire / SiO2 / SiN x Composite substrate, sapphire / SiN x Any one of a / SiO2 composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0104] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A semiconductor laser having a lower waveguide layer for suppressing optical catastrophe, comprising a substrate, a lower cladding layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper cladding layer arranged in sequence from bottom to top, characterized in that: The lower waveguide layer comprises a first optical catastrophe suppression lower waveguide layer, a second optical catastrophe suppression lower waveguide layer and a third optical catastrophe suppression lower waveguide layer which are sequentially arranged from bottom to top, wherein the interface between the first optical catastrophe suppression lower waveguide layer and the lower cladding layer, the interface between the second optical catastrophe suppression lower waveguide layer and the first optical catastrophe suppression lower waveguide layer, and the interface between the third optical catastrophe suppression lower waveguide layer and the second optical catastrophe suppression lower waveguide layer all have bulk elastic modulus distribution characteristics and deformation potential distribution characteristics; The rising angle of the valley position of the bulk elastic modulus of the first optical catastrophe suppression waveguide layer toward the lower cladding layer is α, the falling angle of the peak position of the bulk elastic modulus of the second optical catastrophe suppression waveguide layer toward the lower cladding layer is β, and the rising angle of the valley position of the bulk elastic modulus of the third optical catastrophe suppression waveguide layer toward the lower cladding layer is γ, wherein: 45°≤γ≤β≤α≤90°; The rising angle of the valley position of the deformation potential of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is θ, the falling angle of the peak position of the deformation potential of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is δ, and the rising angle of the valley position of the deformation potential of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is σ, wherein: 40°≤σ≤δ≤θ≤90°.

2. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 1, characterized in that: The interface between the first optical catastrophe suppression lower waveguide layer and the lower cladding layer, the interface between the second optical catastrophe suppression lower waveguide layer and the first optical catastrophe suppression lower waveguide layer, and the interface between the third optical catastrophe suppression lower waveguide layer and the second optical catastrophe suppression lower waveguide layer also have separation energy distribution characteristics and heavy hole effective mass distribution characteristics; The rising angle of the valley position of the separation energy of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is The descending angle of the peak position of the separation energy of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is ψ, and the rising angle of the valley position of the separation energy of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is μ, wherein: The rising angle of the valley position of the heavy hole effective mass of the waveguide layer under the first optical catastrophe suppression toward the lower cladding layer is υ, the descending angle of the peak position of the heavy hole effective mass of the waveguide layer under the second optical catastrophe suppression toward the lower cladding layer is ρ, and the rising angle of the valley position of the heavy hole effective mass of the waveguide layer under the third optical catastrophe suppression toward the lower cladding layer is ω, wherein: 30°≤ω≤ρ≤υ≤90°.

3. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 2, characterized in that: The relationship between the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass of the first optical catastrophe-suppressing waveguide layer toward the lower cladding layer, the bulk elastic modulus, deformation potential, separation energy, and falling angle of the peak position of the heavy hole effective mass of the second optical catastrophe-suppressing waveguide layer toward the lower cladding layer, and the bulk elastic modulus, deformation potential, separation energy, and rising angle of the valley position of the heavy hole effective mass of the third optical catastrophe-suppressing waveguide layer is as follows:

4. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 2, characterized in that: The bulk elastic modulus of the interface between the first optical catastrophe suppression lower waveguide layer and the lower cladding layer has a function y1=D+lnx1+C*e x1 Curve distribution; The deformation potential of the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y2=E+F*e x1 lnx1 curve distribution; The separation energy of the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y3=G+H*e x1 lnx1 curve distribution; The effective mass of heavy holes at the interface between the first optical catastrophe-suppressing waveguide layer and the lower cladding layer has a function y4=J+K*e x1 +x1 curve distribution; Wherein: J≤E≤G≤D, x1 is the depth of the first optical catastrophe suppression lower waveguide layer toward the second optical catastrophe suppression lower waveguide layer.

5. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 2, characterized in that: The bulk elastic modulus of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y5=L+M*e x2 / lnx2 fourth quadrant curve distribution; The deformation potential of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y6=N+M*e x2 / lnx2 fourth quadrant curve distribution; The separation energy of the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y7=P+Q*e x2 / lnx2 fourth quadrant curve distribution; The effective mass of heavy holes at the interface between the second optical catastrophe suppression waveguide layer and the first optical catastrophe suppression waveguide layer has a function y8=R+x2 2 -T*e x2 The third quadrant curve distribution; Wherein: R≤N≤P≤L, x2 is the depth of the second optical catastrophe suppression lower waveguide layer toward the third optical catastrophe suppression lower waveguide layer.

6. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 2, characterized in that: The bulk elastic modulus of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y9=U+V*(e x3 -e -x3 )Limiting curve distribution; The deformation potential of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y 10 =W+x3 -A The second quadrant curve distribution, A is an even number and A>1; The separation energy of the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y 11 =S+x3 -B The second quadrant curve distribution, B is an even number and B>1; The heavy hole effective mass at the interface between the third optical catastrophe suppression waveguide layer and the second optical catastrophe suppression waveguide layer has a function y2=Z+x3lnx3 limited curve distribution; Wherein: Z≤W≤S≤U, x3 is the depth of the waveguide layer toward the active layer under the third optical catastrophe suppression.

7. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 1, characterized in that: The lower waveguide layer is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5nm to 1000nm.

8. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe 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 well layer of the active 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, and has a thickness of The barrier layer of the active 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.

9. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 1, characterized in that: The upper waveguide layer is any one or any combination of InGaN, GaN, InN, AlInGaN, AlInN, AlN, InGaN / GaN superlattice, InGaN / AlGaN superlattice, InGaN / AlInGaN superlattice, InGaN / AlInN superlattice, GaN / AlGaN superlattice, GaN / AlInGaN superlattice, and GaN / AlN superlattice, and has a thickness of 5nm to 1000nm; The lower cladding layer, electron blocking layer and upper cladding layer are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN and diamond.

10. The semiconductor laser having a lower waveguide layer for suppressing optical catastrophe according to claim 1, characterized in that: The substrate includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, graphene, sapphire / SiN x , Sapphire / SiO2 / SiN x Composite substrate, sapphire / SiN x Any one of a / SiO2 composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

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