GaN-based semiconductor laser with limiting factor enhancement layer

Abstract

The invention discloses a GaN-based semiconductor laser with a limiting factor enhancement layer, which sequentially 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 from bottom to top, and is characterized in that the limiting factor enhancement layer is arranged between the electron blocking layer and the upper coating layer; the limiting factor enhancement layer comprises a first limiting factor enhancement layer and a second limiting factor enhancement layer; and the thickness of the limiting factor enhancement layer is 5-1000 nm. According to the invention, refractive index coefficients, electron mobility, breakdown field strength and change angles and change curves of electron affinity of the first limiting factor enhancement layer and the second limiting factor enhancement layer are designed, an effective refractive index difference is regulated and controlled to realize a high kink level, a far-image FFP image with a low aspect ratio is realized, a horizontal divergence angle is reduced, stray light and leakage light are reduced, and the performance of the device is improved. The far-field FFP image with local interference is reduced, and the optical confinement effect and the light beam quality factor are improved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor optoelectronic devices, and in particular to a GaN-based semiconductor laser with a confinement factor enhancement layer. Background Art

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

[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 refractive index dispersion of the laser, the fluctuation of high-concentration carrier concentration affects the refractive index of the active layer, and the confinement factor decreases with increasing wavelength, resulting in a decrease in the mode gain of the laser. The light field of the confinement layer is dissipated, and the light field mode leaks to the substrate to form a standing wave, which leads to low substrate mode suppression efficiency and poor far-field image FFP quality. Summary of the invention

[0005] The present invention proposes a GaN-based semiconductor laser with a confinement factor enhancement layer, designs the change angles and curves of the refractive index coefficient, electron mobility, breakdown field strength, and electron affinity of the first confinement factor enhancement layer and the second confinement factor enhancement layer, regulates the effective refractive index difference to achieve a high kink level, realizes a far-field FFP image with a low aspect ratio, reduces the horizontal divergence angle, reduces stray light and leakage light, reduces the far-field FFP image with local interference, and improves the optical confinement effect and the beam quality factor.

[0006] The present invention provides a GaN-based semiconductor laser with a confinement factor enhancement 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. A confinement factor enhancement layer is provided between the electron blocking layer and the upper cladding layer, and the confinement factor enhancement layer comprises a first confinement factor enhancement layer and a second confinement factor enhancement layer. The confinement factor enhancement layer is any one or any combination of AlGaN, InGaN, GaN, 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 to 1000 nm.

[0007] Preferably, the rising angle of the valley position of the refractive index coefficient of the first confinement factor enhanced layer toward the cladding layer is α, the descending angle of the peak position of the refractive index coefficient of the second confinement factor enhanced layer toward the active layer is β, and the descending angle of the peak position of the refractive index coefficient of the second confinement factor enhanced layer toward the cladding layer is γ, wherein: 45°≤γ≤β≤α≤90°;

[0008] The rising angle of the valley position of the electron mobility of the first confinement factor enhancement layer toward the upper cladding layer is θ, the descending angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the active layer is δ, and the descending angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the upper cladding layer is σ, wherein: 70°≤σ≤δ≤θ≤90°;

[0009] The rising angle of the valley position of the breakdown field strength of the first confinement factor enhancement layer toward the upper cladding layer is φ, the descending angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the active layer is ψ, and the descending angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the upper cladding layer is μ, wherein: 60°≤μ≤ψ≤φ≤90°;

[0010] The rising angle of the valley position of the electron affinity of the first confinement factor enhanced layer toward the upper cladding layer is υ, the decreasing angle of the peak position of the electron affinity of the second confinement factor enhanced layer toward the active layer is ρ, and the decreasing angle of the peak position of the electron affinity of the second confinement factor enhanced layer toward the upper cladding layer is ω, wherein: 65°≤ω≤ρ≤υ≤90°.

[0011] Preferably, the rising angle of the valley position of the Philips ionization degree of the first confinement factor enhanced layer toward the upper cladding layer is ε, the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhanced layer toward the active layer is η, and the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhanced layer toward the upper cladding layer is κ, wherein: 48°≤κ≤η≤ε≤90°;

[0012] The rising angle of the valley position of the spontaneous polarization coefficient of the first confinement factor enhanced layer toward the upper cladding layer is ζ, the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhanced layer toward the active layer is χ, and the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhanced layer toward the upper cladding layer is ν, wherein: 55°≤ν≤χ≤ζ≤90°;

[0013] The descending angle of the peak position of the piezoelectric polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer is τ, the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the active layer is λ, and the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer is ξ, wherein: 50°≤ξ≤λ≤τ≤90°.

[0014] Preferably, the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the first confinement factor enhanced layer have a rising angle in the direction of the cladding layer, and the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer have a descending angle in the direction of the active layer, and the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer have a descending angle in the direction of the active layer. The descending angle of the peak position of the number toward the upper cladding layer, the descending angle of the peak position of the piezoelectric polarization coefficient of the first limitation factor enhancement layer toward the upper cladding layer, the rising angle of the valley position of the piezoelectric polarization coefficient of the second limitation factor enhancement layer toward the active layer, and the rising angle of the valley position of the piezoelectric polarization coefficient of the second limitation factor enhancement layer toward the upper cladding layer have the following relationship: 45°≤γ≤β≤α≤κ≤η≤ε≤ξ≤λ≤τ≤ν≤χ≤ζ≤μ≤ψ≤φ≤ω≤ρ≤υ≤σ≤δ≤θ≤90°.

[0015] Preferably, the refractive index coefficient of the first confinement factor enhancement layer has the function y=x -A (A>1 odd number) first quadrant curve distribution; the electron mobility of the first confinement factor enhancement layer has a function y=x -B (B>1 odd number) first quadrant curve distribution; the breakdown field strength of the first confinement factor enhancement layer has a function y=x -C (C>1 odd number) first quadrant curve distribution; the electron affinity of the first confinement factor enhancement layer has a function y=x -D (D>1 odd number) first quadrant curve distribution; the Philips ionization degree of the first confinement factor enhancement layer has a function y=x -E (E>1 odd number) first quadrant curve distribution; the spontaneous polarization coefficient of the first confinement factor enhancement layer has a function y=x -F (F>1 odd number) first quadrant curve distribution; wherein: 1<B≤D≤C≤F≤E≤A; the piezoelectric polarization coefficient of the first confinement factor enhancement layer has the function y=lnx / e x Curved distribution.

[0016] Preferably, the refractive index coefficient of the second confinement factor enhancement layer has the function y=Gx 2 +Hx+I(G<0) curve distribution; the electron mobility of the second confinement factor enhancement layer has a function y=Jx 2 +Kx+L(J<0) curve distribution; the breakdown field strength of the second confinement factor enhancement layer has a function y=Mx 2 +Nx+O(M<0) curve distribution; the electron affinity of the second confinement factor enhancement layer has a function y=Px 2 +Qx+R(P<0) curve distribution; the Philips ionization degree of the second confinement factor enhancement layer has a function y=Sx 2 +Tx+U(S<0) curve distribution; wherein: G≤S≤M≤P≤J<0; the spontaneous polarization coefficient of the second confinement factor enhancement layer has a function y=x / sinx fourth quadrant curve distribution; the piezoelectric polarization coefficient of the second confinement factor enhancement layer has a function y=x 2 -sinx curve distribution.

[0017] 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 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, Ga 2 O 3 , BN, diamond, any one or any combination thereof, with a thickness of 10 to 150 angstroms, and a barrier layer 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, Ga 2 O 3 , BN, diamond or any combination thereof, with a thickness of 10 to 200 angstroms.

[0018] Preferably, the upper waveguide layer and the 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.

[0019] Preferably, the lower cladding layer, the electron blocking layer, and the upper cladding layer are 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, Ga 2 O 3 , BN, diamond or any combination thereof.

[0020] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO 2 Composite substrates, Mo, TiW, CuW, Cu, sapphire / AlN composite substrates, diamond, graphene, sapphire / SiN x , Sapphire / SiO 2 / SiN x Composite substrate, sapphire / SiN x / SiO 2 Composite substrate, magnesium aluminum spinel MgAl 2 O 4 、MgO、ZnO、ZrB 2 、LiAlO 2 and LiGaO 2 Any type of composite substrate.

[0021] Compared with the prior art, the GaN-based semiconductor laser with a confinement factor enhancement layer provided by the embodiment of the present invention has the following beneficial effects: the change angle and change curve of the refractive index coefficient, electron mobility, breakdown field strength, and electron affinity of the first confinement factor enhancement layer and the second confinement factor enhancement layer are designed, the effective refractive index difference is regulated to achieve a high kink level, a far-field FFP image with a low aspect ratio is achieved, the horizontal divergence angle is reduced, stray light and leakage light are reduced, the far-field FFP image with local interference is reduced, and the optical confinement effect and the beam quality factor are improved; at the same time, the change angle and change curve of the Philips ionization degree, spontaneous polarization coefficient, and piezoelectric polarization coefficient of the first confinement factor enhancement layer and the second confinement factor enhancement layer are designed, the polarization field and electric field of the laser are regulated, the localization of carriers is improved, the free carrier absorption loss is reduced, the relaxation vibration frequency is enhanced, the influence of high-concentration carrier concentration fluctuations on the confinement factor is reduced, and the mode gain, confinement factor, and responsiveness of the laser are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0023] Figure 2 This is a structural SIMS secondary ion mass spectrum of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0024] Figure 3 This is a structural SIMS secondary ion mass spectrum of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0025] Figure 4This is a TEM lens electron microscope image of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0026] Figure 5 This is a TEM lens electron microscope image (partial magnified image) of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0027] Figure 6 This is a TEM lens electron microscope image (partial magnified image) of a GaN-based semiconductor laser with a confinement factor enhancement layer according to an embodiment of the present invention;

[0028] Reference numerals: 100: substrate; 101: lower cladding layer; 102: lower waveguide layer; 103: active layer; 104: upper waveguide layer, 105: electron blocking layer, 106: upper cladding layer; 107: confinement factor enhancing layer. DETAILED DESCRIPTION

[0029] 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.

[0030] In order to solve the above problems, a GaN-based semiconductor laser with a confinement factor enhanced layer provided in an embodiment of the present application will be introduced and explained in detail through the following specific embodiments.

[0031] Reference Figure 1-6 The present invention provides a GaN-based semiconductor laser with a confinement factor enhancement layer, which comprises, 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. A confinement factor enhancement layer 107 is provided between the electron blocking layer 105 and the upper cladding layer 106, and the confinement factor enhancement layer 107 comprises a first confinement factor enhancement layer and a second confinement factor enhancement layer; the confinement factor enhancement layer 107 is any one or any combination of AlGaN, InGaN, GaN, 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 to 1000 nm.

[0032] The rising angle of the valley position of the refractive index coefficient of the first confinement factor enhancement layer toward the cladding layer 106 is α, the descending angle of the peak position of the refractive index coefficient of the second confinement factor enhancement layer toward the active layer 103 is β, and the descending angle of the peak position of the refractive index coefficient of the second confinement factor enhancement layer toward the cladding layer 106 is γ, wherein: 45°≤γ≤β≤α≤90°;

[0033] The rising angle of the valley position of the electron mobility of the first confinement factor enhancement layer toward the upper cladding layer 106 is θ, the descending angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the active layer 103 is δ, and the descending angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the upper cladding layer 106 is σ, wherein: 70°≤σ≤δ≤θ≤90°;

[0034] The rising angle of the valley position of the breakdown field strength of the first confinement factor enhancement layer toward the upper cladding layer 106 is φ, the falling angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the active layer 103 is ψ, and the falling angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the upper cladding layer 106 is μ, wherein: 60°≤μ≤ψ≤φ≤90°;

[0035] The rising angle of the valley position of the electron affinity of the first confinement factor enhanced layer toward the upper cladding layer 106 is υ, the decreasing angle of the peak position of the electron affinity of the second confinement factor enhanced layer toward the active layer 103 is ρ, and the decreasing angle of the peak position of the electron affinity of the second confinement factor enhanced layer toward the upper cladding layer 106 is ω, wherein: 65°≤ω≤ρ≤υ≤90°.

[0036] The rising angle of the valley position of the Philips ionization degree of the first confinement factor enhanced layer toward the upper cladding layer 106 is ε, the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhanced layer toward the active layer 103 is η, and the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhanced layer toward the upper cladding layer 106 is κ, wherein: 48°≤κ≤η≤ε≤90°;

[0037] The rising angle of the valley position of the spontaneous polarization coefficient of the first confinement factor enhancement layer toward the cladding layer 106 is ζ, the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhancement layer toward the active layer 103 is χ, and the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhancement layer toward the cladding layer 106 is ν, wherein: 55°≤ν≤χ≤ζ≤90°;

[0038] The descending angle of the peak position of the piezoelectric polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer 106 is τ, the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the active layer 103 is λ, and the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer 106 is ξ, wherein: 50°≤ξ≤λ≤τ≤90°.

[0039] In summary, the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the first confinement factor enhanced layer have a rising angle in the direction of the upper cladding layer 106, the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer have a falling angle in the direction of the active layer 103, and the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer have a falling angle in the direction of the active layer 103. The descending angle of the peak position toward the upper cladding layer 106, the descending angle of the peak position of the piezoelectric polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer 106, the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the active layer 103, and the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer have the following relationship: 45°≤γ≤β≤α≤κ≤η≤ε≤ξ≤λ≤τ≤ν≤χ≤ζ≤μ≤ψ≤φ≤ω≤ρ≤υ≤σ≤δ≤θ≤90°.

[0040] The refractive index coefficient of the first confinement factor enhancement layer has the function y=x -A (A>1 odd number) first quadrant curve distribution; the electron mobility of the first confinement factor enhancement layer has a function y=x -B (B>1 odd number) first quadrant curve distribution; the breakdown field strength of the first confinement factor enhancement layer has a function y=x -C (C>1 odd number) first quadrant curve distribution; the electron affinity of the first confinement factor enhancement layer has a function y=x -D (D>1 odd number) first quadrant curve distribution; the Philips ionization degree of the first confinement factor enhancement layer has a function y=x -E (E>1 odd number) first quadrant curve distribution; the spontaneous polarization coefficient of the first confinement factor enhancement layer has a function y=x -F (F>1 odd number) first quadrant curve distribution; wherein: 1<B≤D≤C≤F≤E≤A; the piezoelectric polarization coefficient of the first confinement factor enhancement layer has the function y=lnx / e x Curved distribution.

[0041] The refractive index coefficient of the second confinement factor enhancement layer has the function y=Gx 2 +Hx+I(G<0) curve distribution; the electron mobility of the second confinement factor enhancement layer has a function y=Jx 2 +Kx+L(J<0) curve distribution; the breakdown field strength of the second confinement factor enhancement layer has a function y=Mx 2 +Nx+O(M<0) curve distribution; the electron affinity of the second confinement factor enhancement layer has a function y=Px 2 +Qx+R(P<0) curve distribution; the Philips ionization degree of the second confinement factor enhancement layer has a function y=Sx 2 +Tx+U(S<0) curve distribution; wherein: G≤S≤M≤P≤J<0; the spontaneous polarization coefficient of the second confinement factor enhancement layer has a function y=x / sinx fourth quadrant curve distribution; the piezoelectric polarization coefficient of the second confinement factor enhancement layer has a function y=x 2 -sinx curve distribution.

[0042] The present invention designs the change angles and curves of the refractive index coefficients, electron mobility, breakdown field strength, and electron affinity of the first confinement factor enhancement layer and the second confinement factor enhancement layer, regulates the effective refractive index difference to achieve a high kink level, realizes a far-field FFP image with a low aspect ratio, reduces the horizontal divergence angle, reduces stray light and leakage light, reduces the far-field FFP image with local interference, and improves the optical confinement effect and the beam quality factor.

[0043] The present invention designs the change angles and change curves of the Phillips ionization degree, spontaneous polarization coefficient, and piezoelectric polarization coefficient of the first confinement factor enhancement layer and the second confinement factor enhancement layer, regulates the polarization field and electric field of the laser, improves the localization of carriers, reduces free carrier absorption loss, enhances the relaxation vibration frequency, reduces the influence of high-concentration carrier concentration fluctuations on the confinement factor, and improves the mode gain, confinement factor, and responsiveness of the laser.

[0044] The specific data are shown in the following table, which compares the data of the traditional laser and the laser of the present invention.

[0045] Blue Laser Project Conventional laser Laser of the present invention Range of change <![CDATA[Beam quality factor M 2 > 1.89 1.14 66％ Limiting Factor 1.50％ 2.31％ 54％ Horizontal divergence angle 20～50° 5～25°

[0046] 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 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, Ga 2 O 3 , BN, diamond, any one or any combination thereof, with a thickness of 10 to 150 angstroms, and a barrier layer 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, Ga 2 O 3 , BN, diamond or any combination thereof, with a thickness of 10 to 200 angstroms.

[0047] In the present invention, the upper waveguide layer 104 and the lower waveguide layer 102 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.

[0048] In the present invention, the lower cladding layer 101, the electron blocking layer 105, and the upper cladding layer 106 are 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, Ga 2 O 3 , BN, diamond or any combination thereof.

[0049] In the present invention, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO 2 Composite substrates, Mo, TiW, CuW, Cu, sapphire / AlN composite substrates, diamond, graphene, sapphire / SiN x , Sapphire / SiO 2 / SiN x Composite substrate, sapphire / SiN x / SiO 2 Composite substrate, magnesium aluminum spinel MgAl 2 O 4 、MgO、ZnO、ZrB 2 、LiAlO 2 and LiGaO 2 Any type of composite substrate.

[0050] 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 GaN-based semiconductor laser with a confinement factor enhancement layer, 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: A confinement factor enhancement layer (107) is provided between the electron blocking layer (105) and the upper cladding layer (106), and the confinement factor enhancement layer (107) comprises a first confinement factor enhancement layer and a second confinement factor enhancement layer; the confinement factor enhancement layer (107) is any one or any combination of AlGaN, InGaN, GaN, 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 to 1000 nm.

2. A GaN-based semiconductor laser with a confinement factor enhanced layer according to claim 1, characterized in that: The rising angle of the valley position of the refractive index coefficient of the first confinement factor enhancement layer toward the upper cladding layer (106) is α, the falling angle of the peak position of the refractive index coefficient of the second confinement factor enhancement layer toward the active layer (103) is β, and the falling angle of the peak position of the refractive index coefficient of the second confinement factor enhancement layer toward the upper cladding layer (106) is γ, wherein: 45°≤γ≤β≤α≤90°; The rising angle of the valley position of the electron mobility of the first confinement factor enhancement layer toward the upper cladding layer (106) is θ, the falling angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the active layer (103) is δ, and the falling angle of the peak position of the electron mobility of the second confinement factor enhancement layer toward the upper cladding layer (106) is σ, wherein: 70°≤σ≤δ≤θ≤90°; The rising angle of the valley position of the breakdown field strength of the first confinement factor enhancement layer toward the upper cladding layer (106) is φ, the falling angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the active layer (103) is ψ, and the falling angle of the peak position of the breakdown field strength of the second confinement factor enhancement layer toward the upper cladding layer (106) is μ, wherein: 60°≤μ≤ψ≤φ≤90°; The rising angle of the valley position of the electron affinity of the first confinement factor enhancement layer toward the upper cladding layer (106) is υ, the decreasing angle of the peak position of the electron affinity of the second confinement factor enhancement layer toward the active layer (103) is ρ, and the decreasing angle of the peak position of the electron affinity of the second confinement factor enhancement layer toward the upper cladding layer (106) is ω, wherein: 65°≤ω≤ρ≤υ≤90°.

3. A GaN-based semiconductor laser with a confinement factor enhanced layer according to claim 1, characterized in that: The rising angle of the valley position of the Philips ionization degree of the first confinement factor enhancement layer toward the upper cladding layer (106) is ε, the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhancement layer toward the active layer (103) is η, and the descending angle of the peak position of the Philips ionization degree of the second confinement factor enhancement layer toward the upper cladding layer (106) is κ, wherein: 48°≤κ≤η≤ε≤90°; The rising angle of the valley position of the spontaneous polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer (106) is ζ, the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhancement layer toward the active layer (103) is χ, and the descending angle of the peak position of the spontaneous polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer (106) is ν, wherein: 55°≤ν≤χ≤ζ≤90°; The descending angle of the peak position of the piezoelectric polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer (106) is τ, the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the active layer (103) is λ, and the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer (106) is ξ, wherein: 50°≤ξ≤λ≤τ≤90°.

4. A GaN-based semiconductor laser with a confinement factor enhanced layer according to any one of claims 2 to 3, characterized in that: The angle of the valley position of the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the first confinement factor enhanced layer rising toward the upper cladding layer (106), the angle of the peak position of the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer falling toward the active layer (103), and the peak value of the refractive index coefficient, electron mobility, breakdown field strength, electron affinity, Philips ionization degree, and spontaneous polarization coefficient of the second confinement factor enhanced layer. The descending angle of the peak position of the piezoelectric polarization coefficient of the first confinement factor enhancement layer toward the upper cladding layer (106), the descending angle of the peak position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer (106), the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the active layer (103), and the rising angle of the valley position of the piezoelectric polarization coefficient of the second confinement factor enhancement layer toward the upper cladding layer have the following relationship: 45°≤γ≤β≤α≤κ≤η≤ε≤ξ≤λ≤τ≤ν≤χ≤ζ≤μ≤ψ≤φ≤ω≤ρ≤υ≤σ≤δ≤θ≤90°.

5. The GaN-based semiconductor laser with a confinement factor enhanced layer according to claim 1, characterized in that: The refractive index coefficient of the first confinement factor enhancement layer has the function y=x -A (A>1 odd number) first quadrant curve distribution; the electron mobility of the first confinement factor enhancement layer has a function y=x -B (B>1 odd number) first quadrant curve distribution; the breakdown field strength of the first confinement factor enhancement layer has a function y=x -C (C>1 odd number) first quadrant curve distribution; the electron affinity of the first confinement factor enhancement layer has a function y=x -D (D>1 odd number) first quadrant curve distribution; the Philips ionization degree of the first confinement factor enhancement layer has a function y=x -E (E>1 odd number) first quadrant curve distribution; the spontaneous polarization coefficient of the first confinement factor enhancement layer has a function y=x -F (F>1 odd number) first quadrant curve distribution; wherein: 1<B≤D≤C≤F≤E≤A; the piezoelectric polarization coefficient of the first confinement factor enhancement layer has the function y=lnx / e x Curved distribution.

6. The GaN-based semiconductor laser with a confinement factor enhanced layer according to claim 1, characterized in that: The refractive index coefficient of the second confinement factor enhancement layer has the function y=Gx 2 +Hx+I(G<0) curve distribution; the electron mobility of the second confinement factor enhancement layer has a function y=Jx 2 +Kx+L(J<0) curve distribution; the breakdown field strength of the second confinement factor enhancement layer has a function y=Mx 2 +Nx+O(M<0) curve distribution; the electron affinity of the second confinement factor enhancement layer has a function y=Px 2 +Qx+R(P<0) curve distribution; the Philips ionization degree of the second confinement factor enhancement layer has a function y=Sx 2 +Tx+U(S<0) curve distribution; wherein: G≤S≤M≤P≤J<0; the spontaneous polarization coefficient of the second confinement factor enhancement layer has a function y=x / sinx fourth quadrant curve distribution; the piezoelectric polarization coefficient of the second confinement factor enhancement layer has a function y=x 2 -sinx curve distribution.

7. The GaN-based semiconductor laser with a confinement factor enhanced layer 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.

8. The GaN-based semiconductor laser with a confinement factor enhanced layer according to claim 1, characterized in that: The upper waveguide layer (104) and the lower waveguide layer (102) 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.

9. The GaN-based semiconductor laser with a confinement factor enhanced 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.

10. The GaN-based semiconductor laser with a confinement factor enhanced 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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