Semiconductor green laser element

Abstract

The semiconductor green laser element comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer which are sequentially arranged from bottom to top, and an Auger auxiliary light emitting layer is arranged between the active layer and the lower waveguide layer. The Philip ionization degree distribution characteristic and the electron affinity distribution characteristic of the Auger auxiliary light emission layer are limited, the specific Philip ionization degree distribution and the electron affinity distribution have a spin exchange Auger type excitation transfer emission mechanism, and the spin exchange transfer rate exceeds the in-band energy loss and the in-band cooling speed. The Stokes frequency shift loss of the photon energy difference between the pump light and the oscillation light is reduced, the coupling probability from the pump energy level to the laser energy level is increased, the energy loss and waste heat of a laser element are reduced, the uneven distribution of thermal expansion and thermal stress is relieved, and the problems of temperature quenching and laser element breakage are solved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor optoelectronic devices, and in particular to a semiconductor green laser element. 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 Stokes frequency shift loss formed by the photon energy difference between the pump light and the oscillation light is converted into heat, and the energy loss caused by the coupling rate from the pump energy level to the laser upper energy level not being 1 is converted into heat to produce heat loss. The two together produce a large amount of waste heat, which makes the temperature distribution of the laser uneven, causing uneven distribution of thermal expansion and thermal stress, resulting in temperature quenching, laser breakage, thermal lens effect and stress birefringence effect; the thermal lens produces a lens-like phenomenon in space, and the stress birefringence effect changes the polarization state of the incident light, causing the laser beam to be depolarized and distorted. Summary of the invention

[0009] To solve one of the above technical problems, the present invention provides a semiconductor green laser element.

[0010] An embodiment of the present invention provides a semiconductor green laser element, comprising a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper confinement layer arranged in sequence from bottom to top, an Auger-assisted light emission layer is arranged between the active layer and the lower waveguide layer, the Auger-assisted light emission layer has a Philips ionization degree distribution characteristic and an electron affinity energy distribution characteristic, and the Philips ionization degree of the Auger-assisted light emission layer has a function y1=A+B*x 2 +C*sinx curve distribution, the electron affinity of the Auger-assisted light emission layer has a function y2=D+E*sinx / e x Curve distribution, x is the depth of the Auger-assisted light emission layer toward the active layer.

[0011] Preferably, the Auger-assisted light emission layer also has an electron mobility distribution characteristic, and the electron mobility of the Auger-assisted light emission layer has a function y3=F+G*e -x +H*e x Curved distribution.

[0012] Preferably, the Auger-assisted light emission layer also has a conduction band effective state density distribution characteristic, and the conduction band effective state density of the Auger-assisted light emission layer has a function y4=J+K*x 2 sinx first quadrant curve distribution.

[0013] Preferably, the Auger-assisted light emission layer also has a saturated electron drift velocity distribution characteristic, and the saturated electron drift velocity of the Auger-assisted light emission layer has a function y5=ax 2 +bx+c curve distribution, where a>0.

[0014] Preferably, the Auger-assisted light emission layer also has an In / C element ratio distribution characteristic, and the In / C element ratio of the Auger-assisted light emission layer has a function y6=dx 2 +ex+f curve distribution, where d>0.

[0015] Preferably, the Auger-assisted light emission layer also has an In / H element ratio distribution characteristic, and the In / H element ratio of the Auger-assisted light emission layer has a function y7=L+M*e -x +N*e x Curved distribution.

[0016] Preferably, the Auger-assisted light emission layer also has an In / O element ratio distribution characteristic, and the In / O element ratio of the Auger-assisted light emission layer has a function y8=P+Q*x 2 +R*sinx curve distribution.

[0017] Preferably, the Auger-assisted light emission 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, CdSe:Mn, SnS2:Mn, CuSnS2:Mn, CoSnS2:Mn, RMnO5 (R is a rare earth element), and WS2:Mn.

[0018] 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 combination, with a thickness of 10 angstroms to 120 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, and BN, with a thickness of 10 angstroms to 200 angstroms.

[0019] Preferably, the lower limiting layer, the lower waveguide layer, the upper waveguide layer, and the upper limiting 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, and BN.

[0020] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0021] The beneficial effects of the present invention are as follows: the present invention arranges an Auger-assisted light emission layer between the active layer and the lower waveguide layer of the semiconductor green light laser element, and defines the Philips ionization degree distribution characteristics and the electron affinity energy distribution characteristics of the Auger-assisted light emission layer, and the specific Philips ionization degree distribution and the electron affinity energy distribution have a spin exchange Auger excitation transfer emission mechanism, the spin exchange transfer rate exceeds the intra-band energy loss and the intra-band cooling rate, reduces the Stokes frequency shift loss of the photon energy difference between the pump light and the oscillation light, improves the coupling probability from the pump energy level to the laser energy level, reduces the energy loss and waste heat of the laser element, alleviates the uneven distribution of thermal expansion and thermal stress, and improves the temperature quenching and laser element breakage problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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:

[0023] Figure 1 A schematic diagram of the structure of a semiconductor green laser element according to an embodiment of the present invention;

[0024] Figure 2 This is a SIMS secondary ion mass spectrum of the semiconductor green laser element described in an embodiment of the present invention.

[0025] Reference numerals:

[0026] 100. substrate, 101. lower confinement layer, 102. lower waveguide layer, 103. active layer, 104. upper waveguide layer, 105. upper confinement layer, 106. Auger-assisted light emission layer. DETAILED DESCRIPTION

[0027] 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.

[0028] like Figure 1 and Figure 2 As shown, this embodiment provides a semiconductor green laser element, comprising a substrate 100, a lower confinement layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104 and an upper confinement layer 105 arranged in sequence from bottom to top. An Auger-assisted light emission layer 106 is also arranged in the semiconductor green laser element.

[0029] Specifically, in this embodiment, the semiconductor green laser element is provided with a substrate 100, a lower confinement layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104 and an upper confinement layer 105 in order from bottom to top. The Auger-assisted light emission layer 106 is provided between the active layer 103 and the lower waveguide layer 102. In the Auger-assisted light emission layer 106, it has specific Philips ionization degree distribution characteristics and electron affinity energy distribution characteristics, which are specifically manifested as follows:

[0030] (1) Philips ionization degree distribution of the Auger-assisted light emission layer 106

[0031] The Phillips ionization degree of the Auger-assisted light emitting layer 106 has a function y1=A+B*x 2 +C*sinx curve distribution;

[0032] (2) Electron Affinity Distribution of Auger-Assisted Light Emission Layer 106

[0033] The electron affinity of the Auger-assisted light emitting layer 106 has the function y2=D+E*sinx / e x Curve distribution;

[0034] Wherein, x is the depth of the Auger-assisted light emitting layer 106 toward the active layer 103 .

[0035] In this embodiment, an Auger-assisted light emission layer 106 is arranged between the active layer 103 and the lower waveguide layer 102 of the semiconductor green laser element, and the Phillips ionization degree distribution characteristics and the electron affinity energy distribution characteristics of the Auger-assisted light emission layer 106 are limited. The specific Phillips ionization degree distribution and the electron affinity energy distribution have a spin exchange Auger excitation transfer emission mechanism, and the spin exchange transfer rate exceeds the intra-band energy loss and the intra-band cooling rate, thereby reducing the Stokes frequency shift loss of the photon energy difference between the pump light and the oscillation light, improving the coupling probability from the pump energy level to the laser energy level, reducing the energy loss and waste heat of the laser element, alleviating the uneven distribution of thermal expansion and thermal stress, and improving the temperature quenching and laser element breakage problems.

[0036] In some optional embodiments, the Auger-assisted light emission layer 106 also has an electron mobility distribution characteristic, which is specifically manifested as follows: the electron mobility of the Auger-assisted light emission layer 106 has a function y3=F+G*e -x +H*e x Curved distribution.

[0037] In some optional embodiments, the Auger-assisted light emission layer 106 also has a conduction band effective state density distribution characteristic, which is specifically manifested as follows: the conduction band effective state density of the Auger-assisted light emission layer 106 has a function y4=J+K*x 2 sinx first quadrant curve distribution.

[0038] In some optional embodiments, the Auger-assisted light emitting layer 106 also has a saturated electron drift rate distribution characteristic, which is specifically manifested as follows: the saturated electron drift rate of the Auger-assisted light emitting layer 106 has a function y5=ax 2 +bx+c curve distribution, where a>0.

[0039] This embodiment, by limiting the electron mobility distribution characteristics, conduction band effective state density distribution characteristics and saturated electron drift velocity distribution characteristics of the Auger-assisted light emission layer 106, can regulate the carrier distribution and transport of the laser, assist in enhancing the stimulated radiation of the laser element, reduce the excitation threshold of the laser element, reduce the thermal loss of the laser, alleviate the uneven distribution of thermal expansion and thermal stress, improve the thermal lens effect and stress birefringence effect, reduce the depolarization and distortion of the laser beam, and improve the beam quality factor of the laser.

[0040] In some optional embodiments, the Auger-assisted light emitting layer 106 also has an In / C element ratio distribution characteristic, which is specifically manifested as follows: the In / C element ratio of the Auger-assisted light emitting layer 106 has a function y6=dx 2 +ex+f curve distribution, where d>0.

[0041] In some optional embodiments, the Auger-assisted light emitting layer 106 also has an In / H element ratio distribution characteristic, which is specifically manifested as follows: the In / H element ratio of the Auger-assisted light emitting layer 106 has a function y7=L+M*e -x +N*e x Curved distribution.

[0042] In some optional embodiments, the Auger-assisted light emitting layer 106 also has an In / O element ratio distribution characteristic, which is specifically manifested as follows: the In / O element ratio of the Auger-assisted light emitting layer 106 has a function y8=P+Q*x 2 +R*sinx curve distribution.

[0043] This embodiment, by limiting the In / C element ratio distribution characteristics, In / H element ratio distribution characteristics and In / O element ratio distribution characteristics of the Auger-assisted light emitting layer 106, can further improve the photon energy difference between the pump light and the oscillation light, reduce the Stokes frequency shift loss, reduce the energy loss and waste heat of the laser element, improve the problem of uneven temperature distribution, reduce the heat loss of the laser, alleviate the uneven distribution of thermal expansion and thermal stress, improve temperature quenching, laser element breakage, thermal lens effect and stress birefringence effect, reduce the depolarization and distortion of the laser beam, and improve the beam quality factor of the laser.

[0044] In some optional embodiments, the Auger-assisted light emission layer 106 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, CdSe:Mn, SnS2:Mn, CuSnS2:Mn, CoSnS2:Mn, RMnO5 (R is a rare earth element), or WS2:Mn.

[0045] In some optional embodiments, the active layer 103 is a periodic structure composed of a well layer and a barrier layer, and the number of periods is 3≥m≥1.

[0046] 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, and BN, and has a thickness of 10 to 120 angstroms.

[0047] 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, and BN, and has a thickness of 10 to 200 angstroms.

[0048] In some optional embodiments, the lower confinement layer 101, the lower waveguide layer 102, the upper waveguide layer 104, and the upper confinement layer 105 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, and BN.

[0049] In some optional embodiments, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0050] The following table is a parameter comparison between a conventional semiconductor laser element and the semiconductor green laser element proposed in this embodiment, including the beam quality factor, temperature quenching ratio, and laser breakage ratio, showing the difference between the conventional semiconductor laser element and the semiconductor green laser element proposed in this embodiment:

[0051]

[0052] It can be seen that the semiconductor green laser element proposed in this embodiment improves the beam quality factor and reduces the temperature quenching ratio and laser breakage ratio compared with the traditional semiconductor laser element, and has obvious advantages over the traditional semiconductor laser element.

[0053] 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 green laser element, comprising a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper confinement layer arranged in sequence from bottom to top, characterized in that: An Auger-assisted light emission layer is arranged between the active layer and the lower waveguide layer. The Auger-assisted light emission layer has Philips ionization degree distribution characteristics and electron affinity energy distribution characteristics. The Philips ionization degree of the Auger-assisted light emission layer has a function y1=A+B*x 2 +C*sinx curve distribution, the electron affinity of the Auger-assisted light emission layer has the function y2=D+E*sinx / e x Curve distribution, x is the depth of the Auger-assisted light emission layer toward the active layer.

2. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has an electron mobility distribution characteristic. The electron mobility of the Auger-assisted light emission layer has a function y3=F+G*e -x +H*e x Curved distribution.

3. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has a conduction band effective state density distribution characteristic. The conduction band effective state density of the Auger-assisted light emission layer has a function y4=J+K*x 2 sinx first quadrant curve distribution.

4. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has a saturated electron drift rate distribution characteristic. The saturated electron drift rate of the Auger-assisted light emission layer has a function y5=ax 2 +bx+c curve distribution, where a>0.

5. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has an In / C element ratio distribution characteristic. The In / C element ratio of the Auger-assisted light emission layer has a function y6=dx 2 +ex+f curve distribution, where d>0.

6. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has an In / H element ratio distribution characteristic. The In / H element ratio of the Auger-assisted light emission layer has a function y7=L+M*e -x +N*e x Curved distribution.

7. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission layer also has an In / O element ratio distribution characteristic. The In / O element ratio of the Auger-assisted light emission layer has a function y8=P+Q*x 2 +R*sinx curve distribution.

8. The semiconductor green laser element according to claim 1, characterized in that: The Auger-assisted light emission 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, CdSe:Mn, SnS2:Mn, CuSnS2:Mn, CoSnS2:Mn, RMnO5 (R is a rare earth element), and WS2:Mn.

9. The semiconductor green laser element according to claim 1, characterized in that: 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 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, and BN , with a thickness of 10 angstroms to 120 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, and BN, with a thickness of 10 angstroms to 200 angstroms.

10. The semiconductor green laser element according to claim 6, characterized in that: The lower confinement layer, the lower waveguide layer, the upper waveguide layer, and the upper confinement 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, and BN; The substrate includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

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