Gallium nitride-based semiconductor laser chip element

Abstract

The gallium nitride-based semiconductor laser chip element comprises a substrate and an epitaxial layer, the epitaxial layer is arranged on the upper layer of the substrate, an antireflection layer is plated on the surface of a first cavity surface of the epitaxial layer, and a high reflection layer is plated on the surface of a second cavity surface of the epitaxial layer. The antireflection layer comprises a first sub-antireflection layer, a plurality of second sub-antireflection layers and a plurality of third sub-antireflection layers which are sequentially plated on the surface of the first cavity surface, and the plurality of second sub-antireflection layers and the plurality of third sub-antireflection layers are sequentially and alternately arranged to form a periodic structure; the antireflection layer comprises a plurality of peak electric field intensities and a plurality of valley electric field intensities, the maximum value of the plurality of peak electric field intensities is located in the middle area of the antireflection layer, and the electric field intensities are gradually reduced from the middle area to the two sides. The quantum efficiency of the laser can be improved, and the threshold current density can be reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor optoelectronic devices, and in particular to a gallium nitride-based semiconductor laser chip component. 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 light field is far away from the active area and close to the electron blocking layer, which will cause optical loss, reduce the quantum well's carrier confinement, and produce electron leakage; abnormal light field distribution will cause light field leakage, increase the laser's diffraction efficiency, increase the vertical divergence angle, reduce the beam quality, and reduce the light field confinement factor. Summary of the invention

[0009] In order to solve one of the above technical problems, the present invention provides a gallium nitride-based semiconductor laser chip component.

[0010] An embodiment of the present invention provides a gallium nitride-based semiconductor laser chip element, comprising a substrate and an epitaxial layer, wherein the epitaxial layer is arranged on an upper layer of the substrate, and the left and right sides of the epitaxial layer are respectively a first cavity surface and a second cavity surface, and the first cavity surface is located at the far end of the laser emission direction, and the second cavity surface is located at the near end of the laser emission direction, the surface of the first cavity surface is plated with an anti-reflection layer, and the surface of the second cavity surface is plated with a high reflection layer, the anti-reflection layer comprises a first sub-anti-reflection layer, a multi-layer second sub-anti-reflection layer, and a multi-layer third sub-anti-reflection layer sequentially plated on the surface of the first cavity surface, and the multi-layer second sub-anti-reflection layer and the multi-layer third sub-anti-reflection layer are alternately arranged in sequence to form a periodic structure, the electric field intensity of the simulated light field distribution of the anti-reflection layer is a periodic oscillation distribution, the anti-reflection layer comprises a plurality of peak electric field intensities and a plurality of valley electric field intensities, the maximum value of the plurality of peak electric field intensities is located in the middle region of the anti-reflection layer, and the electric field intensity gradually decreases from the middle region to both sides.

[0011] Preferably, the reflectivity of the anti-reflection layer is 60% to 85% when the laser wavelength is 500nm to 535nm, and the reflectivity of the high-reflection layer is 95% to 100% when the laser wavelength is 500nm to 535nm.

[0012] Preferably, the number of anti-reflection layers is 6 to 15.

[0013] Preferably, the number of layers of the anti-reflection layer is 8, the anti-reflection layer includes 5 peak electric field intensities, the first cavity surface includes 2 peak electric field intensities, the first peak electric field intensity and the second peak electric field intensity are located in the first cavity surface, the third peak electric field intensity is located in the first layer of the second sub-anti-reflection layer, the fourth peak electric field intensity is located in the first layer of the third sub-anti-reflection layer, and the fourth peak electric field intensity is the maximum value among the peak electric field intensities, the fifth peak electric field intensity is located at the interface area between the second layer of the second sub-anti-reflection layer and the second layer of the third sub-anti-reflection layer, the sixth peak electric field intensity is located at the interface area between the third layer of the second sub-anti-reflection layer and the third layer of the third sub-anti-reflection layer, the seventh peak electric field intensity is located at the interface area between the fourth layer of the second sub-anti-reflection layer and the air, and the fourth peak electric field intensity ≥ the second peak electric field intensity ≥ the first peak electric field intensity ≥ the third valley electric field intensity ≥ the fifth valley electric field intensity ≥ the sixth peak electric field intensity ≥ the seventh peak electric field intensity.

[0014] Preferably, the ratio of the fourth peak electric field strength divided by the second peak electric field strength is a: 1≤a≤2.0, the ratio of the fourth peak electric field strength divided by the first peak electric field strength is b: 1.2≤b≤1.8, the ratio of the fourth peak electric field strength divided by the third peak electric field strength is c: 1.5≤c≤2.5, the ratio of the fourth peak electric field strength divided by the fifth peak electric field strength is d: 1.5≤d≤4, the ratio of the fourth peak electric field strength divided by the sixth peak electric field strength is e: 2.0≤e≤10, the ratio of the fourth peak electric field strength divided by the seventh peak electric field strength is f: 5≤f≤100, and a≤b≤c≤d≤e≤f.

[0015] Preferably, the number of layers of the anti-reflection layer is 8, the anti-reflection layer includes 5 valley electric field intensities, the first cavity surface includes 1 valley electric field strength, the first valley electric field strength is located in the first cavity surface, the second valley electric field strength is located in the first sub-anti-reflection layer, the third valley electric field strength is located in the first second sub-anti-reflection layer, the fourth valley electric field strength is located at the interface area between the first third sub-anti-reflection layer and the second second sub-anti-reflection layer, the fifth valley electric field strength is located at the interface area between the second third sub-anti-reflection layer and the third second sub-anti-reflection layer, the sixth valley electric field strength is located at the interface area between the third third sub-anti-reflection layer and the fourth second sub-anti-reflection layer, and the sixth valley electric field strength is ≥ the fifth valley electric field strength ≥ the fourth valley electric field strength ≥ the third valley electric field strength ≥ the second valley electric field strength ≥ the first valley electric field strength.

[0016] Preferably, the number of layers of the anti-reflection layer is 8;

[0017] The electric field intensity of the first cavity surface has a curve distribution of function y1=asin(bx1+c)+d;

[0018] The electric field intensity of the first sub-anti-reflection layer has a function y2=fcos(gx2+h)+i curve distribution;

[0019] The electric field intensity of the second anti-reflection sub-layer of the first layer has a curve distribution of function y3=jsin(kx3+m)+n;

[0020] The electric field intensity of the first third sub-antireflection layer has a function y4=psin(qx4+r)+s curve distribution;

[0021] The electric field intensity of the second sub-anti-reflection layer of the second layer has a curve distribution of function y5=tsin(ux5+v)+w;

[0022] The electric field intensity of the second third sub-anti-reflection layer has a function y6=Vsin(Wx6+O)+Z curve distribution;

[0023] The electric field intensity of the third second sub-anti-reflection layer has a curve distribution of function y7=Jsin(Kx7+L)+M;

[0024] The electric field intensity of the third anti-reflection sub-layer of the third layer has a function y8=Ncos(Px8+L)+Q curve distribution;

[0025] The electric field intensity of the fourth second sub-anti-reflection layer has a function y9=Rsin(Sx9+T)+U curve distribution;

[0026] Wherein, x1 is the thickness of the epitaxial layer, x2 is the thickness of the first sub-anti-reflection layer, x3 is the thickness of the first second sub-anti-reflection layer, x4 is the thickness of the first third sub-anti-reflection layer, x5 is the thickness of the second second sub-anti-reflection layer, x6 is the thickness of the second third sub-anti-reflection layer, x7 is the thickness of the third second sub-anti-reflection layer, x8 is the thickness of the third third sub-anti-reflection layer, x9 is the thickness of the fourth second sub-anti-reflection layer, U≤Q≤M≤Z≤w≤n≤d≤i≤s, R≤N≤J≤V≤t≤j≤a≤f≤p.

[0027] Preferably, the first sub-anti-reflection layer is Al2O3, the second sub-anti-reflection layer is Ta2O5 or SiO2, and the third sub-anti-reflection layer is SiN x or SiO2.

[0028] Preferably, the number of layers of the anti-reflection layer is 8, when the second sub-anti-reflection layer is Ta2O5 and the third sub-anti-reflection layer is SiO2, the quarter wavelengths of the first sub-anti-reflection layer, the first second sub-anti-reflection layer, the first third sub-anti-reflection layer, the second second sub-anti-reflection layer, the second third sub-anti-reflection layer, the third second sub-anti-reflection layer, the third third sub-anti-reflection layer and the fourth second sub-anti-reflection layer are 0.8 to 1.2, 1.9 to 2.3, 1.5 to 1.9, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, and 0.8 to 1.2 respectively, and the quarter wavelength of the first sub-anti-reflection layer is ≤ the quarter wavelength of the fourth second sub-anti-reflection layer ≤ the quarter wavelength of the third second sub-anti-reflection layer ≤ the quarter wavelength of the second second sub-anti-reflection layer ≤ the quarter wavelength of the third third sub-anti-reflection layer ≤ the quarter wavelength of the second third sub-anti-reflection layer ≤ the quarter wavelength of the first third sub-anti-reflection layer ≤ the quarter wavelength of the first second sub-anti-reflection layer.

[0029] Preferably, the epitaxial layer includes a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper confinement layer, which are arranged in sequence from bottom to top, and the epitaxial 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.

[0030] 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.

[0031] The beneficial effects of the present invention are as follows: the present invention is provided with an anti-reflection layer and a high-reflection layer on the cavity surfaces on both sides of the epitaxial layer of the gallium nitride-based semiconductor laser chip element. The anti-reflection layer comprises a first sub-anti-reflection layer, a multi-layer second sub-anti-reflection layer and a multi-layer third sub-anti-reflection layer sequentially plated on the surface of the first cavity surface, and the multi-layer second sub-anti-reflection layer and the multi-layer third sub-anti-reflection layer are alternately arranged in sequence to form a periodic structure, the electric field intensity of the simulated light field distribution of the anti-reflection layer is a periodic oscillation distribution, the anti-reflection layer comprises a plurality of peak electric field intensities and a plurality of valley electric field intensities, the maximum value of the plurality of peak electric field intensities is located in the middle region of the anti-reflection layer, and the electric field intensity gradually decreases from the middle region to both sides. The present invention can move the light field distribution from near the p-type side waveguide to near the n-type side waveguide, so that the light field of the active layer falls on the n-type side close to the n-type side, enhance the carrier confinement of the quantum well, inhibit electron leakage, reduce free carrier loss, and reduce the overlap ratio of the light field with the highly doped p-type electron blocking layer and the upper confinement layer, reduce light absorption loss, inhibit Joule heat, reduce the temperature of the active layer, improve the quantum efficiency of the laser and reduce the threshold current density. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] 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:

[0033] Figure 1 A schematic diagram of the structure of a gallium nitride-based semiconductor laser chip element according to an embodiment of the present invention;

[0034] Figure 2 Schematic diagram of the structure of the anti-reflection layer according to an embodiment of the present invention, with 8 layers;

[0035] Figure 3 Schematic diagram of the structure of the anti-reflection layer according to an embodiment of the present invention, with 10 layers;

[0036] Figure 4 Schematic diagram of the structure of the anti-reflection layer according to an embodiment of the present invention, with 11 layers;

[0037] Figure 5 This is an electric field intensity distribution diagram of a simulated light field distribution of a gallium nitride-based semiconductor laser chip element according to an embodiment of the present invention, and the number of anti-reflection layers is 8;

[0038] Figure 6 It is a schematic diagram of the structure of the epitaxial layer described in an embodiment of the present invention.

[0039] Reference numerals:

[0040] 100, substrate, 101, epitaxial layer, 102, anti-reflection layer, 103, high reflection layer;

[0041] 1011, first cavity surface, 1012, second cavity surface;

[0042] 1021, a first sub-anti-reflection layer, 1022, a second sub-anti-reflection layer, 1023, a third sub-anti-reflection layer. DETAILED DESCRIPTION

[0043] 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.

[0044] like Figure 1As shown, this embodiment proposes a gallium nitride-based semiconductor laser chip element, including a substrate 100 and an epitaxial layer 101. The epitaxial layer 101 is arranged on the upper layer of the substrate 100. The left and right sides of the epitaxial layer 101 are respectively a first cavity surface 1011 and a second cavity surface 1012. Among them, the first cavity surface 1011 is located at the far end of the laser emission direction, and the second cavity surface 1012 is located at the near end of the laser emission direction. An anti-reflection layer 102 is plated on the surface of the first cavity surface 1011. A high reflection layer 103 is plated on the surface of the second cavity surface 1012.

[0045] Specifically, in this embodiment, the anti-reflection layer 102 on the surface of the first cavity surface 1011 includes a first sub-anti-reflection layer 1021, a multi-layer second sub-anti-reflection layer 1022, and a multi-layer third sub-anti-reflection layer 1023, which are sequentially plated on the surface of the first cavity surface 1011. The multi-layer second sub-anti-reflection layer 1022 and the multi-layer third sub-anti-reflection layer 1023 are alternately arranged in sequence to form a periodic structure, such as Figure 2 The structure schematic diagram of the anti-reflection layer 102 formed by alternately arranging four layers of the second sub-anti-reflection layer 1022 and three layers of the third sub-anti-reflection layer 1023 in sequence is shown (the figure is only a schematic diagram and does not represent the actual size). In the anti-reflection layer 102, the electric field intensity presents a periodic oscillation distribution, and the anti-reflection layer 102 includes a plurality of peak electric field intensities and a plurality of valley electric field intensities, wherein the maximum value of the plurality of peak electric field intensities is located in the middle region of the anti-reflection layer 102, and the electric field intensity gradually decreases from the middle region to both sides (the first cavity surface 1011 side and the air side).

[0046] In this embodiment, an anti-reflection layer 102 and a high-reflection layer 103 are respectively plated on the cavity surfaces on both sides of the epitaxial layer 101 of the gallium nitride-based semiconductor laser chip element. The anti-reflection layer 102 includes a first sub-anti-reflection layer 1021, a plurality of second sub-anti-reflection layers 1022, and a plurality of third sub-anti-reflection layers 1023, which are sequentially plated on the surface of the first cavity surface 1011, and the plurality of second sub-anti-reflection layers 1022 and the plurality of third sub-anti-reflection layers 1023 are alternately arranged in sequence to form a periodic structure, and the electric field strength of the anti-reflection layer 102 is a periodic oscillation distribution, and the anti-reflection layer 102 includes a plurality of peak electric field strengths and a plurality of valley electric field strengths, wherein the maximum value of the plurality of peak electric field strengths is located in the middle region of the anti-reflection layer 102, and the electric field strength gradually decreases from the middle region to both sides (the first cavity surface 1011 side and the air side). The present invention can move the light field distribution from near the p-type side waveguide to near the n-type side waveguide, so that the light field of the active layer falls on the n-type side close to the n-type side, enhance the carrier confinement of the quantum well, inhibit electron leakage, reduce free carrier loss, and reduce the overlap ratio of the light field with the highly doped p-type electron blocking layer and the upper confinement layer, reduce light absorption loss, inhibit Joule heat, reduce the temperature of the active layer, improve the quantum efficiency of the laser and reduce the threshold current density.

[0047] In some optional embodiments, the number of layers of the anti-reflection layer 102 can be designed to be 6 to 15 layers. Among them, the first sub-anti-reflection layer 1021 is fixed to 1 layer, and the number of the second sub-anti-reflection layer 1022 and the third sub-anti-reflection layer 1023 can be determined according to the total number of layers of the anti-reflection layer 102. If the number of layers of the anti-reflection layer 102 is 8 layers, then the first sub-anti-reflection layer 1021 is 1 layer, the second sub-anti-reflection layer 1022 is 4 layers, and the third sub-anti-reflection layer 1023 is 3 layers, and the second sub-anti-reflection layer 1022 and the third sub-anti-reflection layer 1023 are alternately arranged in sequence, such as Figure 2 If the number of layers of the anti-reflection layer 102 is 10, then the first sub-anti-reflection layer 1021 is 1 layer, the second sub-anti-reflection layer 1022 is 5 layers, and the third sub-anti-reflection layer 1023 is 4 layers, and the second sub-anti-reflection layer 1022 and the third sub-anti-reflection layer 1023 are alternately arranged in sequence, as shown in FIG. Figure 3 If the number of layers of the anti-reflection layer 102 is 11, then the first sub-anti-reflection layer 1021 is 1 layer, the second sub-anti-reflection layer 1022 is 5 layers, and the third sub-anti-reflection layer 1023 is 5 layers, and the second sub-anti-reflection layer 1022 and the third sub-anti-reflection layer 1023 are alternately arranged in sequence, as shown in FIG. Figure 4 shown.

[0048] In this embodiment, the electric field intensity distribution on the anti-reflection layer 102 is different according to the number of anti-reflection layers 102 .

[0049] Specifically, taking the anti-reflection layer 102 having 8 layers as an example, the distribution of the peak electric field intensity in the first cavity surface and the anti-reflection layer is as follows: Figure 5 As shown. On the first cavity surface 1011 of the epitaxial layer 101, there are two peak electric field intensities, which are respectively recorded as the first peak electric field intensity 104 and the second peak electric field intensity 105. In the first layer of the second sub-anti-reflection layer 1022, there is a peak electric field intensity, which is recorded as the third peak electric field intensity 106. In the first layer of the third sub-anti-reflection layer 1023, there is a peak electric field intensity, which is recorded as the fourth peak electric field intensity 107, and the fourth peak electric field intensity is also the maximum value of all peak electric field intensities in the first cavity surface and the anti-reflection layer. The interface region between the second layer of the second sub-anti-reflection layer 1022 and the second layer of the third sub-anti-reflection layer 1023 includes a peak electric field intensity, which is recorded as the fifth peak electric field intensity 108. The interface region between the third layer of the second sub-anti-reflection layer 1022 and the third layer of the third sub-anti-reflection layer 1023 includes a peak electric field intensity, which is recorded as the sixth peak electric field intensity 109. The interface region between the fourth second anti-reflection sub-layer 1022 and the air includes one peak electric field intensity, which is recorded as the seventh peak electric field intensity 110 .

[0050] In this embodiment, since the electric field strength of the anti-reflection layer 102 is a periodic oscillation distribution, the maximum value of the multiple peak electric field strengths is located in the middle area of ​​the anti-reflection layer 102, and the electric field strength gradually decreases from the middle area to both sides (the first cavity surface 1011 side and the air side). Therefore, all the above peak electric field strengths have the following relationship:

[0051] Fourth peak electric field strength 107 ≥ second peak electric field strength 105 ≥ first peak electric field strength 104 ≥ third valley electric field strength 106 ≥ fifth valley electric field strength 108 ≥ sixth peak electric field strength 109 ≥ seventh peak electric field strength 110 .

[0052] Furthermore, the ratio of the fourth peak electric field strength 107 divided by the second peak electric field strength 105 is a: 1≤a≤2.0, the ratio of the fourth peak electric field strength 107 divided by the first peak electric field strength 104 is b: 1.2≤b≤1.8, the ratio of the fourth peak electric field strength 107 divided by the third peak electric field strength 106 is c: 1.5≤c≤2.5, the ratio of the fourth peak electric field strength 107 divided by the fifth peak electric field strength 108 is d: 1.5≤d≤4, the ratio of the fourth peak electric field strength 107 divided by the sixth peak electric field strength 109 is e: 2.0≤e≤10, the ratio of the fourth peak electric field strength 107 divided by the seventh peak electric field strength 110 is f: 5≤f≤100, and a≤b≤c≤d≤e≤f.

[0053] At the same time, the distribution of the valley electric field intensity in the first cavity surface and the anti-reflection layer is still the same as Figure 5 As shown. On the first cavity surface 1011 of the epitaxial layer 101, there is a valley electric field intensity, recorded as the first valley electric field intensity 111. In the first sub-anti-reflection layer 1021, there is a valley electric field intensity, recorded as the second valley electric field intensity 112. In the first layer of the second sub-anti-reflection layer 1022, there is a valley electric field intensity, recorded as the third valley electric field intensity 113. The interface region between the first layer of the third sub-anti-reflection layer 1023 and the second layer of the second sub-anti-reflection layer 1022 includes a valley electric field intensity, recorded as the fourth valley electric field intensity 114. The interface region between the second layer of the third sub-anti-reflection layer 1023 and the third layer of the second sub-anti-reflection layer 1022 includes a valley electric field intensity, recorded as the fifth valley electric field intensity 115. The interface region between the third third anti-reflection sub-layer 1023 and the fourth second anti-reflection sub-layer 1022 includes one valley electric field intensity, which is recorded as a sixth valley electric field intensity 116 .

[0054] The first layer of the third sub-anti-reflection layer 1023 includes a peak electric field intensity, which is recorded as the fourth peak electric field intensity 107, and the fourth peak electric field intensity is also the maximum value of all peak electric field intensities in the first cavity surface and the anti-reflection layer. The interface region between the second layer of the second sub-anti-reflection layer 1022 and the second layer of the third sub-anti-reflection layer 1023 includes a peak electric field intensity, which is recorded as the fifth peak electric field intensity 108. The interface region between the third layer of the second sub-anti-reflection layer 1022 and the third layer of the third sub-anti-reflection layer 1023 includes a peak electric field intensity, which is recorded as the sixth peak electric field intensity 109. The interface region between the fourth layer of the second sub-anti-reflection layer 1022 and the air includes a peak electric field intensity, which is recorded as the seventh peak electric field intensity 110.

[0055] In this embodiment, since the electric field strength of the anti-reflection layer 102 is a periodic oscillation distribution, the maximum value of the multiple peak electric field strengths is located in the middle region of the anti-reflection layer 102, and the electric field strength gradually decreases from the middle region to both sides (the first cavity surface 1011 side and the air side). Therefore, all the above valley electric field strengths have the following relationship:

[0056] The sixth valley electric field strength 116 ≥ the fifth valley electric field strength 115 ≥ the fourth valley electric field strength 114 ≥ the third valley electric field strength 113 ≥ the second valley electric field strength 112 ≥ the first valley electric field strength 111 .

[0057] This embodiment improves the light field distribution, reduces light field leakage, enhances the light field confinement factor, and enhances the beam quality factor by regulating the electric field intensity distribution of the laser cavity surface and the anti-reflection layer; regulates the QWOT and distribution of the anti-reflection layer, reduces the diffraction efficiency of the laser, reduces the vertical divergence angle, and improves the far-field image quality.

[0058] In some optional embodiments, the first cavity surface and each sub-anti-reflection layer of the anti-reflection layer have specific electric field intensity distribution characteristics. Taking the anti-reflection layer as an example with 8 layers, the electric field intensity distribution in the first cavity surface and each sub-anti-reflection layer is as follows:

[0059] The electric field intensity of the first cavity surface 1011 has a curve distribution of function y1=asin(bx1+c)+d;

[0060] The electric field intensity of the first sub-anti-reflection layer 1021 has a curve distribution of function y2=fcos(gx2+h)+i;

[0061] The electric field intensity of the first second anti-reflection sub-layer 1022 has a curve distribution of function y3=jsin(kx3+m)+n;

[0062] The electric field intensity of the first third anti-reflection sub-layer 1023 has a function y4=psin(qx4+r)+s curve distribution;

[0063] The electric field intensity of the second second anti-reflection sub-layer 1022 has a curve distribution of function y5=tsin(ux5+v)+w;

[0064] The electric field intensity of the second third anti-reflection sub-layer 1023 has a function y6=Vsin(Wx6+O)+Z curve distribution;

[0065] The electric field intensity of the third second sub-anti-reflection layer 1022 has a curve distribution of function y7=Jsin(Kx7+L)+M;

[0066] The electric field intensity of the third anti-reflection sub-layer 1023 has a function y8=Ncos(Px8+L)+Q curve distribution;

[0067] The electric field intensity of the fourth second anti-reflection sub-layer 1022 has a curve distribution of function y9=Rsin(Sx9+T)+U;

[0068] Wherein, x1 is the thickness of the epitaxial layer 101, x2 is the thickness of the first sub-anti-reflection layer 1021, x3 is the thickness of the first second sub-anti-reflection layer 1022, x4 is the thickness of the first third sub-anti-reflection layer 1023, x5 is the thickness of the second second sub-anti-reflection layer 1022, x6 is the thickness of the second third sub-anti-reflection layer 1023, x7 is the thickness of the third second sub-anti-reflection layer 1022, x8 is the thickness of the third third sub-anti-reflection layer 1023, x9 is the thickness of the fourth second sub-anti-reflection layer 1022, U≤Q≤M≤Z≤w≤n≤d≤i≤s, R≤N≤J≤V≤t≤j≤a≤f≤p.

[0069] In some optional embodiments, the reflectivity of the anti-reflection layer 102 is 60% to 85% when the laser wavelength is 500nm to 535nm, and the reflectivity of the high-reflection layer 103 is 95% to 100% when the laser wavelength is 500nm to 535nm.

[0070] In some optional embodiments, the first sub-anti-reflection layer 1021 is Al2O3, the second sub-anti-reflection layer 1022 is Ta2O5 or SiO2, and the third sub-anti-reflection layer 1023 is SiN x or SiO2.

[0071] Specifically, each material has a refractive index η. The refractive index η is the ratio of the speed of light in a vacuum to the speed of light in a medium. The wavelength of light in a medium is given by the equation λ=λ0 / η, where λ0 is the wavelength of light in a vacuum. QWOT=λ0 / 4η is used to determine a quarter wavelength in a layer of a medium. Therefore, in this embodiment, the quarter wavelength QWOT of the first sub-anti-reflection layer 102, the second sub-anti-reflection layer 1022, and the third sub-anti-reflection layer 1023 made of different materials will also be different. This embodiment is still specifically described by taking the number of layers of the anti-reflection layer 102 as 8 layers as an example.

[0072] When the number of layers of the anti-reflection layer 102 is 8, the second sub-anti-reflection layer 1022 is Ta2O5, and the third sub-anti-reflection layer 1023 is SiO2, the quarter wavelengths of the first sub-anti-reflection layer 1021, the first second sub-anti-reflection layer 1022, the first third sub-anti-reflection layer 1023, the second second sub-anti-reflection layer 1022, the second third sub-anti-reflection layer 1023, the third second sub-anti-reflection layer 1022, the third third sub-anti-reflection layer 1023 and the fourth second sub-anti-reflection layer 1022 are 0.8 to 1.2, 1.9 to 2.3, 1.5 to 1.9, 0.8 to 1. 2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, one-quarter wavelength of the first sub-anti-reflection layer 1021 ≤ one-quarter wavelength of the fourth second sub-anti-reflection layer 1022 ≤ one-quarter wavelength of the third second sub-anti-reflection layer 1022 ≤ one-quarter wavelength of the second second sub-anti-reflection layer 1022 ≤ one-quarter wavelength of the third third sub-anti-reflection layer 1023 ≤ one-quarter wavelength of the second third sub-anti-reflection layer 1023 ≤ one-quarter wavelength of the first third sub-anti-reflection layer 1023 ≤ one-quarter wavelength of the first second sub-anti-reflection layer 1022.

[0073] In some optional embodiments, the epitaxial layer 101 includes a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper confinement layer arranged in sequence from bottom to top, such as Figure 6 The epitaxial layer 101 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.

[0074] In some optional embodiments, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, graphene, sapphire / SiN x , Sapphire / SiO2 / SiN x Composite substrate, sapphire / SiN x Any one of a / SiO2 composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0075] The following table is a parameter comparison between a conventional gallium nitride-based semiconductor laser chip component and the gallium nitride-based semiconductor laser chip component proposed in this embodiment, including stimulated emission quantum efficiency, threshold current density, limitation factor, internal optical loss, beam quality factor, and focused spot resolution, showing the difference between the conventional gallium nitride-based semiconductor laser chip component and the gallium nitride-based semiconductor laser chip component proposed in this embodiment:

[0076]

[0077] It can be seen that the gallium nitride-based semiconductor laser chip element proposed in this embodiment has improved the stimulated radiation quantum efficiency and limitation factor, reduced the threshold current density, internal optical loss and beam quality factor, and significantly improved the focused spot resolution compared with traditional gallium nitride-based semiconductor laser chip elements. It has obvious advantages over traditional gallium nitride-based semiconductor laser chip elements.

[0078] 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 gallium nitride-based semiconductor laser chip component, comprising a substrate and an epitaxial layer, wherein the epitaxial layer is arranged on the upper layer of the substrate, characterized in that: The left and right sides of the epitaxial layer are respectively the first cavity surface and the second cavity surface, and the first cavity surface is located at the far end of the laser emission direction, and the second cavity surface is located at the near end of the laser emission direction. The surface of the first cavity surface is plated with an anti-reflection layer, and the surface of the second cavity surface is plated with a high reflection layer. The anti-reflection layer includes a first sub-anti-reflection layer, a multi-layer second sub-anti-reflection layer, and a multi-layer third sub-anti-reflection layer sequentially plated on the surface of the first cavity surface, and the multi-layer second sub-anti-reflection layer and the multi-layer third sub-anti-reflection layer are alternately arranged in sequence to form a periodic structure. The electric field intensity of the simulated light field distribution of the anti-reflection layer is a periodic oscillation distribution. The anti-reflection layer includes multiple peak electric field intensities and multiple valley electric field intensities. The maximum value of the multiple peak electric field intensities is located in the middle area of ​​the anti-reflection layer, and the electric field intensity gradually decreases from the middle area to both sides.

2. The gallium nitride-based semiconductor laser chip component according to claim 1, characterized in that: The reflectivity of the anti-reflection layer is 60% to 85% when the laser wavelength is 500nm to 535nm, and the reflectivity of the high-reflection layer is 95% to 100% when the laser wavelength is 500nm to 535nm.

3. The gallium nitride-based semiconductor laser chip element according to claim 1, characterized in that: The number of layers of the anti-reflection layer is 6 to 15.

4. The gallium nitride-based semiconductor laser chip element according to claim 3, characterized in that: The number of layers of the anti-reflection layer is 8, the anti-reflection layer includes 5 peak electric field intensities, the first cavity surface includes 2 peak electric field intensities, the first peak electric field intensity and the second peak electric field intensity are located in the first cavity surface, the third peak electric field intensity is located in the first layer of the second sub-anti-reflection layer, the fourth peak electric field intensity is located in the first layer of the third sub-anti-reflection layer, and the fourth peak electric field intensity is the maximum value among the peak electric field intensities, the fifth peak electric field intensity is located in the interface area between the second layer of the second sub-anti-reflection layer and the second layer of the third sub-anti-reflection layer, the sixth peak electric field intensity is located in the interface area between the third layer of the second sub-anti-reflection layer and the third layer of the third sub-anti-reflection layer, the seventh peak electric field intensity is located in the interface area between the fourth layer of the second sub-anti-reflection layer and the air, and the fourth peak electric field intensity ≥ the second peak electric field intensity ≥ the first peak electric field intensity ≥ the third valley electric field intensity ≥ the fifth valley electric field intensity ≥ the sixth peak electric field intensity ≥ the seventh peak electric field intensity.

5. The gallium nitride-based semiconductor laser chip element according to claim 4, characterized in that: The ratio of the fourth peak electric field strength divided by the second peak electric field strength is a: 1≤a≤2.0, the ratio of the fourth peak electric field strength divided by the first peak electric field strength is b: 1.2≤b≤1.8, the ratio of the fourth peak electric field strength divided by the third peak electric field strength is c: 1.5≤c≤2.5, the ratio of the fourth peak electric field strength divided by the fifth peak electric field strength is d: 1.5≤d≤4, the ratio of the fourth peak electric field strength divided by the sixth peak electric field strength is e: 2.0≤e≤10, the ratio of the fourth peak electric field strength divided by the seventh peak electric field strength is f: 5≤f≤100, and a≤b≤c≤d≤e≤f.

6. The gallium nitride-based semiconductor laser chip element according to claim 3, characterized in that: The number of layers of the anti-reflection layer is 8, the anti-reflection layer includes 5 valley electric field strengths, the first cavity surface includes 1 valley electric field strength, the first valley electric field strength is located in the first cavity surface, the second valley electric field strength is located in the first sub-anti-reflection layer, the third valley electric field strength is located in the first second sub-anti-reflection layer, the fourth valley electric field strength is located in the interface region between the first third sub-anti-reflection layer and the second second sub-anti-reflection layer, the fifth valley electric field strength is located in the interface region between the second third sub-anti-reflection layer and the third second sub-anti-reflection layer, the sixth valley electric field strength is located in the interface region between the third third sub-anti-reflection layer and the fourth second sub-anti-reflection layer, and the sixth valley electric field strength is ≥ the fifth valley electric field strength ≥ the fourth valley electric field strength ≥ the third valley electric field strength ≥ the second valley electric field strength ≥ the first valley electric field strength.

7. The gallium nitride-based semiconductor laser chip element according to claim 3, characterized in that: The number of layers of the anti-reflection layer is 8; The electric field intensity of the first cavity surface has a curve distribution of function y1=asin(bx1+c)+d; The electric field intensity of the first sub-anti-reflection layer has a function y2=fcos(gx2+h)+i curve distribution; The electric field intensity of the second anti-reflection sub-layer of the first layer has a curve distribution of function y3=jsin(kx3+m)+n; The electric field intensity of the third anti-reflection sub-layer of the first layer has a function y4=psin(qx4+r)+s curve distribution; The electric field intensity of the second sub-anti-reflection layer of the second layer has a curve distribution of function y5=tsin(ux5+v)+w; The electric field intensity of the second third sub-anti-reflection layer has a function y6=Vsin(Wx6+O)+Z curve distribution; The electric field intensity of the third second sub-anti-reflection layer has a curve distribution of function y7=Jsin(Kx7+L)+M; The electric field intensity of the third anti-reflection sub-layer of the third layer has a function y8=Ncos(Px8+L)+Q curve distribution; The electric field intensity of the fourth second sub-anti-reflection layer has a function y9=Rsin(Sx9+T)+U curve distribution; Wherein, x1 is the thickness of the epitaxial layer, x2 is the thickness of the first sub-anti-reflection layer, x3 is the thickness of the first second sub-anti-reflection layer, x4 is the thickness of the first third sub-anti-reflection layer, x5 is the thickness of the second second sub-anti-reflection layer, x6 is the thickness of the second third sub-anti-reflection layer, x7 is the thickness of the third second sub-anti-reflection layer, x8 is the thickness of the third third sub-anti-reflection layer, x9 is the thickness of the fourth second sub-anti-reflection layer, U≤Q≤M≤Z≤w≤n≤d≤i≤s, R≤N≤J≤V≤t≤j≤a≤f≤p.

8. The gallium nitride-based semiconductor laser chip element according to claim 3, characterized in that: The first sub-anti-reflection layer is Al2O3, the second sub-anti-reflection layer is Ta2O5 or SiO2, and the third sub-anti-reflection layer is SiN x or SiO2.

9. The gallium nitride-based semiconductor laser chip element according to claim 3, characterized in that: The number of layers of the anti-reflection layer is 8, when the second sub-anti-reflection layer is Ta2O5 and the third sub-anti-reflection layer is SiO2, a quarter wavelength of the first sub-anti-reflection layer, the first second sub-anti-reflection layer, the first third sub-anti-reflection layer, the second second sub-anti-reflection layer, the second third sub-anti-reflection layer, the third second sub-anti-reflection layer, the third third sub-anti-reflection layer and the fourth second sub-anti-reflection layer are 0.8 to 1.2, 1.9 to 2.3, 1.5 to 1.9, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, 0.8 to 1.2, and 0.8 to 1.2, respectively, and a quarter wavelength of the first sub-anti-reflection layer ≤ a quarter wavelength of the fourth second sub-anti-reflection layer ≤ a quarter wavelength of the third second sub-anti-reflection layer ≤ a quarter wavelength of the second second sub-anti-reflection layer ≤ a quarter wavelength of the third third sub-anti-reflection layer ≤ a quarter wavelength of the second third sub-anti-reflection layer ≤ a quarter wavelength of the first third sub-anti-reflection layer ≤ a quarter wavelength of the first second sub-anti-reflection layer.

10. The gallium nitride-based semiconductor laser chip component according to claim 1, characterized in that: The epitaxial layer comprises a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper confinement layer which are arranged in sequence from bottom to top, and the epitaxial 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; The substrate includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, Mo, TiW, CuW, Cu, sapphire / AlN composite substrate, diamond, graphene, sapphire / SiN x , Sapphire / SiO2 / SiN x Composite substrate, sapphire / SiN x Any one of a / SiO2 composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

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