Gallium nitride-based semiconductor laser with upper limit waveguide layer for limiting light field

Abstract

The gallium nitride-based 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 in sequence from bottom to top, the lower waveguide layer is a limited light field lower waveguide layer, the upper waveguide layer is a limited light field upper waveguide layer, and the electron blocking layer is an electron blocking layer. The limited light field lower waveguide layer comprises a first limited light field lower waveguide layer and a second limited light field lower waveguide layer; the limited light field upper waveguide layer comprises a first limited light field upper waveguide layer and a second limited light field upper waveguide layer. The limiting effect of heterojunction barriers of the upper waveguide layer and the lower waveguide layer of the laser on carriers is regulated and controlled, carrier transportation and distribution are controlled, highly degenerate electron-hole composite stimulated radiation is limited in the direction deviating to the lower waveguide layer, light field dissipation and permeation are reduced, the carriers and photons are effectively limited in the active layer, and the efficiency of the laser is improved. And the light field limiting factor of the laser is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor optoelectronic devices, and in particular to a gallium nitride-based semiconductor laser with an upper waveguide layer that limits an optical field. 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 significant differences between lasers and nitride semiconductor light-emitting diodes. 1) Lasers are generated by stimulated radiation from carriers, with a small half-width spectrum and high brightness. The output power of a single laser can be in the W level, while nitride semiconductor light-emitting diodes emit 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 as high as 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) The light-emitting diode spontaneously radiates, without external influence, and is incoherent light that transitions from high energy level to low energy level, while the laser is stimulated transition radiation, and the energy of the induced photon should be equal to the difference in energy levels of the electron transition, generating photons and induced photons with identical coherent light; 4) The principles are different: the light-emitting diode is under the action of external voltage, and the electron-hole transition to the active layer or pn junction generates radiation recombination and luminescence, while the laser needs the lasing conditions to be met before it can be lased, and the carrier inversion distribution in the active area 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, and the threshold condition is met so that the gain is greater than the loss, and finally the laser is output.

[0004] Nitride semiconductor lasers have the following problems: the substrate mode is manifested as a small laser spot divergence angle, the far-field image does not satisfy the Gaussian pattern in the c-axis direction of the laser epitaxial layer, the spot quality is poor, and it cannot be focused; the light field is dissipated, and the light field mode leaks into the substrate to form a standing wave, which will lead to low substrate mode suppression efficiency and poor far-field image FFP quality. Summary of the invention

[0005] The present invention provides a gallium nitride-based semiconductor laser with a waveguide layer for limiting an upper limit of an optical field, which solves the problems existing in the prior art.

[0006] The present invention provides a gallium nitride-based semiconductor laser with a limiting light field upper waveguide layer, which comprises, from bottom to top, 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, wherein the lower waveguide layer is a limiting light field lower waveguide layer, the upper waveguide layer is a limiting light field upper waveguide layer, the limiting light field lower waveguide layer comprises a first limiting light field lower waveguide layer and a second limiting light field lower waveguide layer; the limiting light field upper waveguide layer comprises a first limiting light field upper waveguide layer and a second limiting light field upper waveguide layer; the The waveguide layer above the confined light field and the waveguide layer below the confined light field are 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 the thickness is 5 to 1000 nm.

[0007] Preferably, the descending angle of the peak position of the electron affinity of the waveguide layer under the first confining light field toward the lower cladding layer is α, the rising angle of the valley position of the electron affinity of the waveguide layer under the second confining light field toward the lower cladding layer is β, the descending angle of the peak position of the electron affinity of the waveguide layer in the first confining light field toward the upper cladding layer is γ, and the descending angle of the peak position of the electron affinity of the waveguide layer in the second confining light field toward the upper cladding layer is θ, wherein: 45°≤θ≤α≤β≤γ≤90°.

[0009] Preferably, the descending angle of the peak position of the Philips ionization degree of the waveguide layer under the first confining light field toward the lower cladding layer is δ, the rising angle of the valley position of the Philips ionization degree of the waveguide layer under the second confining light field toward the lower cladding layer is σ, the descending angle of the peak position of the Philips ionization degree of the waveguide layer above the first confining light field toward the upper cladding layer is φ, and the descending angle of the peak position of the Philips ionization degree of the waveguide layer above the second confining light field toward the upper cladding layer is ψ, wherein: 40°≤ψ≤δ≤σ≤φ≤90°.

[0010] Preferably, the descending angle of the peak position of the breakdown field intensity of the waveguide layer under the first limiting light field toward the lower cladding layer is μ, the rising angle of the valley position of the breakdown field intensity of the waveguide layer under the second limiting light field toward the lower cladding layer is υ, the descending angle of the peak position of the breakdown field intensity of the waveguide layer in the first limiting light field toward the upper cladding layer is ρ, and the descending angle of the peak position of the breakdown field intensity of the waveguide layer in the second limiting light field toward the upper cladding layer is ω, wherein: 50°≤ω≤μ≤υ≤ρ≤90°.

[0011] Preferably, the rising angle of the valley position of the conduction band effective state density of the waveguide layer under the first limiting light field toward the lower cladding layer is η, the falling angle of the peak position of the conduction band effective state density of the waveguide layer under the second limiting light field toward the lower cladding layer is κ, the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the first limiting light field toward the upper cladding layer is ζ, and the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the second limiting light field toward the upper cladding layer is χ, wherein: 5°≤χ≤η≤κ ≤ζ≤90°; the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer is ν, the descending angle of the peak position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer is π, the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer is τ, and the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer is λ, wherein: 35°≤λ≤ν≤π≤τ≤90.

[0012] Preferably, the angle of decrease of the peak position of the electron affinity, Philips ionization degree and breakdown field strength of the waveguide layer under the first limiting light field toward the lower cladding layer, the angle of increase of the valley position of the electron affinity, Philips ionization degree and breakdown field strength of the waveguide layer under the second limiting light field toward the lower cladding layer, the angle of decrease of the peak position of the electron affinity, Philips ionization degree and breakdown field strength of the waveguide layer on the first limiting light field toward the upper cladding layer, the angle of decrease of the peak position of the electron affinity, Philips ionization degree and breakdown field strength of the waveguide layer on the second limiting light field toward the upper cladding layer, the conduction band effective The relationship between the rising angle of the valley position of the state density and the thermal expansion coefficient toward the cladding layer below, the falling angle of the conduction band effective state density and the peak position of the thermal expansion coefficient toward the cladding layer below the second limiting light field, the rising angle of the conduction band effective state density and the valley position of the thermal expansion coefficient toward the cladding layer above the first limiting light field, and the rising angle of the conduction band effective state density and the valley position of the thermal expansion coefficient toward the cladding layer above the second limiting light field are as follows: 35°≤λ≤ν≤π≤τ≤ψ≤δ≤σ≤φ≤θ≤α≤β≤γ≤ω≤μ≤υ≤ρ≤χ≤η≤κ≤ζ≤90°.

[0013] Preferably, the electron affinity energy distribution of the waveguide layer under the first confining light field has a function y=a1+b1*x -A (A>1 odd number) third quadrant curve shape distribution; Philips ionization degree distribution of the waveguide layer under the first confining light field has function y=c1+d1*x -B (B>1 odd number) third quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the first confined light field has the function y=f1+g1*x-C (C>1 odd number) the third quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the first confining light field has the function y=h1+j1*x -D (D>1 even number) second quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the first confined light field has the function y=k1+l1*x -E (E>even number) second quadrant curve shape distribution; wherein: E≤B≤A≤C≤D, a1, b1, c1, d1, f1, g1, h1, j1, k1, l1 are arbitrary values; the electron affinity energy distribution of the waveguide layer under the second confining light field has the function y=m1+n1*x -F (F>even number) second quadrant curve distribution; the Philips ionization degree distribution of the waveguide layer under the second confining light field has a function y=q1+p1*x -G (G>even number) second quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the second confined light field has the function y=r1+s1*x -H (H>even number) second quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the second confining light field has a function y=t1+u1*x -J (J>1 odd number) third quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the second confined light field has the function y=v1+w1*x -K (Odd number K>1) The third quadrant curve shape distribution; wherein: K≤G≤F≤H≤J, m1, n1, p1, q1, r1, s1, t1, u1, v1, w1 are arbitrary values.

[0014] Preferably, the electron affinity energy distribution of the waveguide layer on the first confining light field has a function y=a2+b2*log a x(a>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the first confining light field has a function y=c2+d2*log b x(b>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the first confined light field has a function y=f2+g2*log c x(c>1) curve shape distribution; the electron affinity energy distribution of the waveguide layer on the second confining light field has the function y=h2+j2*log d x(d>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the second confining light field has a function y=k2+l2*log f x(f>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the second confined light field has a function y=m2+n2*log gx(g>1) curve shape distribution; wherein: f≤d≤g≤b≤a≤c, a2, b2, c2, d2, f2, g2, h2, j2, k2, l2, m2, n2 are arbitrary values; the conduction band effective state density distribution of the waveguide layer on the first confining light field has the function y=p2+q2*x -M (M>0) first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the first confined light field has a function y=r2+s2*x -N (N>0) the first quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer on the second confining light field has a function y=t2+u2*x -P (P>0) the first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the second confined light field has the function y=v2+w2*x -Q (Q>0) first quadrant curve shape distribution; where: Q≤N≤P≤M, p2, q2, r2, s2, t2, u2, v2, w2 are arbitrary values.

[0015] Preferably, the active layer 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, diamond combination, with a thickness of 10 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, with a thickness of 10 to 200 angstroms.

[0016] 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.

[0017] 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.

[0018] Compared with the prior art, the gallium nitride-based semiconductor laser with a waveguide layer that limits the upper limit of the light field provided by the embodiment of the present invention has the beneficial effects that: the present invention designs the change angle and the shape distribution of the change curve of the electron affinity, the Philips ionization degree, and the conduction band effective state density, regulates the limiting effect of the heterojunction barrier of the upper waveguide layer and the lower waveguide layer of the laser on the carriers, controls the carrier transport and distribution, limits the stimulated radiation of the highly degenerate electron-hole recombination to the direction of the lower waveguide layer, reduces the light field dispersion and penetration, effectively limits the carriers and photons in the active layer, and improves the light field limiting factor of the laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of a gallium nitride-based semiconductor laser having an upper limit waveguide layer for limiting an optical field according to an embodiment of the present invention;

[0020] Figure 2 This is a structural SIMS secondary ion mass spectrum of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0021] Figure 3 This is a structural SIMS secondary ion mass spectrum of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0022] Figure 4 This is a TEM lens electron microscope image of a gallium nitride-based semiconductor laser having a light field upper limit waveguide layer according to an embodiment of the present invention;

[0023] Figure 5 This is a TEM lens electron microscope image (partial magnified image) of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0024] Figure 6 This is a TEM lens electron microscope image (partial magnified image) of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0025] Figure 7 This is a TEM lens electron microscope image (partial magnified image) of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0026] Figure 8 This is a TEM lens electron microscope image (partial magnified image) of a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer according to an embodiment of the present invention;

[0027] In the figure, markings are as follows: 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. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In order to solve the above problems, a gallium nitride-based semiconductor laser with a light field upper limit waveguide layer provided in an embodiment of the present application will be introduced and explained in detail through the following specific embodiments.

[0030] Reference Figure 1-8The present invention provides a gallium nitride-based semiconductor laser with a limiting light field upper limit waveguide layer, which includes, from bottom to top, 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. The lower waveguide layer 102 is a limiting light field lower waveguide layer, the upper waveguide layer 104 is a limiting light field upper waveguide layer, the limiting light field lower waveguide layer includes a first limiting light field lower waveguide layer and a second limiting light field lower waveguide layer; the limiting light field upper waveguide layer includes a first limiting light field upper waveguide layer and a waveguide layer on the second confining light field; the waveguide layer on the confining light field and the waveguide layer under the confining light field are 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 the thickness is 5 to 1000 nm.

[0031] The descending angle of the peak position of the electron affinity of the waveguide layer under the first confining light field toward the lower cladding layer 101 is α, the rising angle of the valley position of the electron affinity of the waveguide layer under the second confining light field toward the lower cladding layer 101 is β, the descending angle of the peak position of the electron affinity of the waveguide layer on the first confining light field toward the upper cladding layer 106 is γ, and the descending angle of the peak position of the electron affinity of the waveguide layer on the second confining light field toward the upper cladding layer 106 is θ, wherein: 45°≤θ≤α≤β≤γ≤90°. The descending angle of the peak position of the Philips ionization degree of the waveguide layer under the first confining light field toward the lower cladding layer 101 is δ, the rising angle of the valley position of the Philips ionization degree of the waveguide layer under the second confining light field toward the lower cladding layer 101 is σ, the descending angle of the peak position of the Philips ionization degree of the waveguide layer on the first confining light field toward the upper cladding layer 106 is φ, and the descending angle of the peak position of the Philips ionization degree of the waveguide layer on the second confining light field toward the upper cladding layer 106 is ψ, wherein: 40°≤ψ≤δ≤σ≤φ≤90°. The descending angle of the peak position of the breakdown field intensity of the waveguide layer under the first limiting light field toward the lower cladding layer 101 is μ, the rising angle of the valley position of the breakdown field intensity of the waveguide layer under the second limiting light field toward the lower cladding layer 101 is υ, the descending angle of the peak position of the breakdown field intensity of the waveguide layer on the first limiting light field toward the upper cladding layer 106 is ρ, and the descending angle of the peak position of the breakdown field intensity of the waveguide layer on the second limiting light field toward the upper cladding layer 106 is ω, wherein: 50°≤ω≤μ≤υ≤ρ≤90°. The rising angle of the valley position of the conduction band effective state density of the waveguide layer under the first limiting light field toward the lower cladding layer 101 is η, the falling angle of the peak position of the conduction band effective state density of the waveguide layer under the second limiting light field toward the lower cladding layer 101 is κ, the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the first limiting light field toward the upper cladding layer 106 is ζ, and the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the second limiting light field toward the upper cladding layer 106 is χ, wherein: 55°≤χ≤η≤κ≤ζ ≤90°; the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer 101 is ν, the descending angle of the peak position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer 101 is π, the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer 106 is τ, and the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer 106 is λ, wherein: 35°≤λ≤ν≤π≤τ≤90.

[0032] In summary, the first limiting light field is the descending angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer in the direction of the lower cladding layer 101, the second limiting light field is the rising angle of the valley position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer in the direction of the lower cladding layer 101, the first limiting light field is the descending angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer in the direction of the upper cladding layer 106, the second limiting light field is the descending angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer in the direction of the upper cladding layer 106, the first limiting light field is the conduction band effective The rising angle of the valley position of the state density and the thermal expansion coefficient toward the lower cladding layer 101, the descending angle of the conduction band effective state density and the peak position of the thermal expansion coefficient of the waveguide layer under the second limiting light field toward the lower cladding layer 101, the rising angle of the conduction band effective state density and the valley position of the thermal expansion coefficient of the waveguide layer on the first limiting light field toward the upper cladding layer 106, and the rising angle of the conduction band effective state density and the valley position of the thermal expansion coefficient of the waveguide layer on the second limiting light field toward the upper cladding layer 106 have the following relationship: 35°≤λ≤ν≤π≤τ≤ψ≤δ≤σ≤φ≤θ≤α≤β≤γ≤ω≤μ≤υ≤ρ≤χ≤η≤κ≤ζ≤90°.

[0033] The electron affinity energy distribution of the waveguide layer under the first confining light field has a function y=a1+b1*x -A (A>1 odd number) third quadrant curve shape distribution; Philips ionization degree distribution of the waveguide layer under the first confining light field has function y=c1+d1*x -B (B>1 odd number) third quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the first confined light field has the function y=f1+g1*x -C (C>1 odd number) the third quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the first confining light field has the function y=h1+j1*x -D (D>1 even number) second quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the first confined light field has the function y=k1+l1*x -E (E>even number) second quadrant curve shape distribution; wherein: E≤B≤A≤C≤D, a1, b1, c1, d1, f1, g1, h1, j1, k1, l1 are arbitrary values; the electron affinity energy distribution of the waveguide layer under the second confining light field has the function y=m1+n1*x -F (F>even number) second quadrant curve distribution; the Philips ionization degree distribution of the waveguide layer under the second confining light field has a function y=q1+p1*x -G(G>even number) second quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the second confined light field has the function y=r1+s1*x -H (H>even number) second quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the second confining light field has a function y=t1+u1*x -J (J>1 odd number) third quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the second confined light field has the function y=v1+w1*x -K (Odd number K>1) The third quadrant curve shape distribution; wherein: K≤G≤F≤H≤J, m1, n1, p1, q1, r1, s1, t1, u1, v1, w1 are arbitrary values.

[0034] The electron affinity energy distribution of the waveguide layer on the first confined light field has a function y=a2+b2*log a x(a>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the first confining light field has a function y=c2+d2*log b x(b>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the first confined light field has a function y=f2+g2*log c x(c>1) curve shape distribution; the electron affinity energy distribution of the waveguide layer on the second confining light field has the function y=h2+j2*log d x(d>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the second confining light field has a function y=k2+l2*log f x(f>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the second confined light field has a function y=m2+n2*log g x(g>1) curve shape distribution; wherein: f≤d≤g≤b≤a≤c, a2, b2, c2, d2, f2, g2, h2, j2, k2, l2, m2, n2 are arbitrary values; the conduction band effective state density distribution of the waveguide layer on the first confining light field has the function y=p2+q2*x -M (M>0) first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the first confined light field has a function y=r2+s2*x -N (N>0) the first quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer on the second confining light field has a function y=t2+u2*x -P (P>0) the first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the second confined light field has the function y=v2+w2*x -Q (Q>0) first quadrant curve shape distribution; where: Q≤N≤P≤M, p2, q2, r2, s2, t2, u2, v2, w2 are arbitrary values.

[0035] The invention designs the change angle and change curve shape distribution of electron affinity, Philips ionization degree and conduction band effective state density, regulates the limiting effect of heterojunction potential barriers of upper waveguide layer and lower waveguide layer of the laser on carriers, controls carrier transport and distribution, limits the stimulated radiation of highly degenerate electron-hole recombination in the direction of the lower waveguide layer, reduces light field dispersion and penetration, effectively limits carriers and photons in the active layer, and improves the light field limiting factor of the laser; at the same time, designs the change angle and change curve shape distribution of breakdown field intensity and thermal expansion coefficient, suppresses the refractive index dispersion of the laser, suppresses the leakage of light field mode to the substrate to form standing waves, makes the far-field image approach Gaussian distribution in the c-axis direction, improves the resolution of the concentrated light spot, reduces the vertical divergence angle, and improves the light spot quality and beam quality factor.

[0036] The specific data are shown in the following table, which compares the data of the traditional laser and the laser of the present invention.

[0037] Blue Laser Project Conventional laser Laser of the present invention Range of change <![CDATA[Beam quality factor M 2 > 1.89 1.09 73％ Limiting Factor 1.50％ 2.43％ 62％ Focus spot resolution (nm) >200 <20 Vertical divergence 65-80° 30～65°

[0038] In the present invention, 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 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 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.

[0039] In the present invention, 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.

[0040] In the present invention, 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.

[0041] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A gallium nitride-based semiconductor laser having a waveguide layer for limiting an optical field, comprising, from bottom to top, 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), characterized in that: The lower waveguide layer (102) is a confined light field lower waveguide layer, and the upper waveguide layer (104) is a confined light field upper waveguide layer, the confined light field lower waveguide layer comprises a first confined light field lower waveguide layer and a second confined light field lower waveguide layer; the confined light field upper waveguide layer comprises a first confined light field upper waveguide layer and a second confined light field upper waveguide layer; the confined light field upper waveguide layer and the confined light field lower waveguide layer are 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 have a thickness of 5 to 1000 nm.

2. A gallium nitride-based semiconductor laser with a waveguide layer for limiting the optical field according to claim 1, characterized in that: The descending angle of the peak position of the electron affinity of the waveguide layer under the first confining light field toward the lower cladding layer (101) is α, the rising angle of the valley position of the electron affinity of the waveguide layer under the second confining light field toward the lower cladding layer (101) is β, the descending angle of the peak position of the electron affinity of the waveguide layer on the first confining light field toward the upper cladding layer (106) is γ, and the descending angle of the peak position of the electron affinity of the waveguide layer on the second confining light field toward the upper cladding layer (106) is θ, wherein: 45°≤θ≤α≤β≤γ≤90°.

3. The gallium nitride-based semiconductor laser with a waveguide layer for limiting the optical field according to claim 1, characterized in that: The descending angle of the peak position of the Philips ionization degree of the waveguide layer under the first confining light field toward the lower cladding layer (101) is δ, the rising angle of the valley position of the Philips ionization degree of the waveguide layer under the second confining light field toward the lower cladding layer (101) is σ, the descending angle of the peak position of the Philips ionization degree of the waveguide layer on the first confining light field toward the upper cladding layer (106) is φ, and the descending angle of the peak position of the Philips ionization degree of the waveguide layer on the second confining light field toward the upper cladding layer (106) is ψ, wherein: 40°≤ψ≤δ≤σ≤φ≤90°.

4. The gallium nitride-based semiconductor laser with a light field limiting waveguide layer according to claim 1, characterized in that: The descending angle of the peak position of the breakdown field intensity of the waveguide layer under the first limiting light field toward the lower cladding layer (101) is μ, the rising angle of the valley position of the breakdown field intensity of the waveguide layer under the second limiting light field toward the lower cladding layer (101) is υ, the descending angle of the peak position of the breakdown field intensity of the waveguide layer on the first limiting light field toward the upper cladding layer (106) is ρ, and the descending angle of the peak position of the breakdown field intensity of the waveguide layer on the second limiting light field toward the upper cladding layer (106) is ω, wherein: 50°≤ω≤μ≤υ≤ρ≤90°.

5. The gallium nitride-based semiconductor laser with a light field limiting waveguide layer according to claim 1, characterized in that: The rising angle of the valley position of the conduction band effective state density of the waveguide layer under the first limiting light field toward the lower cladding layer (101) is η, the falling angle of the peak position of the conduction band effective state density of the waveguide layer under the second limiting light field toward the lower cladding layer (101) is κ, the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the first limiting light field toward the upper cladding layer (106) is ζ, and the rising angle of the valley position of the conduction band effective state density of the waveguide layer on the second limiting light field toward the upper cladding layer (106) is χ, wherein: 55°≤χ≤η≤κ≤ζ ≤90°; the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer (101) is ν, the descending angle of the peak position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer (101) is π, the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the first limiting light field toward the cladding layer (106) is τ, and the rising angle of the valley position of the thermal expansion coefficient of the waveguide layer in the second limiting light field toward the cladding layer (106) is λ, wherein: 35°≤λ≤ν≤π≤τ≤90.

6. A gallium nitride-based semiconductor laser having a light field limiting waveguide layer according to any one of claims 2 to 5, characterized in that: The first limiting light field is a decreasing angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer toward the lower cladding layer (101); the second limiting light field is a decreasing angle of the valley position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer toward the lower cladding layer (101); the first limiting light field is a decreasing angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer toward the upper cladding layer (106); the second limiting light field is a decreasing angle of the peak position of the electron affinity, Philips ionization degree, and breakdown field strength of the waveguide layer toward the upper cladding layer (106); the first limiting light field is a decreasing angle of the conduction band effective state density of the waveguide layer. The relationship between the angle of increase of the valley value of the thermal expansion coefficient and the conduction band effective state density of the waveguide layer in the second limiting light field and the direction of the cladding layer (101) downward is as follows: 35°≤λ≤ν≤π≤τ≤ψ≤δ≤σ≤φ≤θ≤α≤β≤γ≤ω≤μ≤υ≤ρ≤χ≤η≤κ≤ζ≤90°.

7. The gallium nitride-based semiconductor laser with a light field limiting waveguide layer according to claim 1, characterized in that: The electron affinity energy distribution of the waveguide layer under the first confining light field has a function y=a1+b1*x -A (A>1 odd number) third quadrant curve shape distribution; Philips ionization degree distribution of the waveguide layer under the first confining light field has function y=c1+d1*x -B (B>1 odd number) third quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the first confined light field has the function y=f1+g1*x -C (C>1 odd number) the third quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the first confining light field has the function y=h1+j1*x -D (D>1 even number) second quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the first confined light field has the function y=k1+l1*x -E (E>even number) second quadrant curve shape distribution; Where: E≤B≤A≤C≤D, a1, b1, c1, d1, f1, g1, h1, j1, k1, l1 are arbitrary values; the electron affinity energy distribution of the waveguide layer under the second confining light field has the function y=m1+n1*x -F (F>even number) second quadrant curve distribution; the Philips ionization degree distribution of the waveguide layer under the second confining light field has a function y=q1+p1*x -G (G>even number) second quadrant curve shape distribution; the breakdown field intensity distribution of the waveguide layer under the second confined light field has a function y=r1+s1*x -H (H>even number) second quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer under the second confining light field has a function y=t1+u1*x -J (J>1 odd number) third quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer under the second confined light field has the function y=v1+w1*x -K (K>1 odd number) third quadrant curve shape distribution; wherein: K≤G≤F≤H≤J, m1, n1, p1, q1, r1, s1, t1, u1, v1, w1 are arbitrary values.

8. A gallium nitride-based semiconductor laser having a light field upper limit waveguide layer according to any one of claims 1, characterized in that: The electron affinity energy distribution of the waveguide layer on the first confined light field has a function y=a2+b2*log a x(a>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the first confining light field has a function y=c2+d2*log b x(b>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the first confined light field has a function y=f2+g2*log c x(c>1) curve shape distribution; the electron affinity energy distribution of the waveguide layer on the second confining light field has the function y=h2+j2*log d x(d>1) curve shape distribution; the Philips ionization degree distribution of the waveguide layer on the second confining light field has a function y=k2+l2*log f x(f>1) curve shape distribution; the breakdown field intensity distribution of the waveguide layer on the second confined light field has a function y=m2+n2*log g x(g>1) curve shape distribution; Wherein: f≤d≤g≤b≤a≤c, a2, b2, c2, d2, f2, g2, h2, j2, k2, l2, m2, n2 are arbitrary values; the effective state density distribution of the conduction band of the waveguide layer on the first confining light field has the function y=p2+q2*x -M (M>0) first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the first confined light field has a function y=r2+s2*x -N (N>0) the first quadrant curve shape distribution; the conduction band effective state density distribution of the waveguide layer on the second confining light field has a function y=t2+u2*x -P (P>0) the first quadrant curve shape distribution; the thermal expansion coefficient distribution of the waveguide layer on the second confined light field has the function y=v2+w2*x -Q (Q>0) first quadrant curve shape distribution; where: Q≤N≤P≤M, p2, q2, r2, s2, t2, u2, v2, w2 are arbitrary values.

9. The gallium nitride-based semiconductor laser with a waveguide layer for limiting the optical field according to claim 1, characterized in that: 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 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, diamond or the like. Any 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.

10. The gallium nitride-based semiconductor laser with a light field limiting waveguide layer according to claim 1, characterized in that: 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.

11. The gallium nitride-based semiconductor laser with a light field limiting waveguide layer according to claim 1, characterized in that: 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.

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