Dual-band semiconductor laser device and preparation method thereof

Abstract

The invention relates to a dual-band semiconductor laser device and a preparation method thereof, and belongs to the technical field of semiconductors. The dual-band semiconductor laser device sequentially comprises a substrate, a buffer layer, a first lower limiting layer, a first lower waveguide layer, a first quantum well, a first upper waveguide layer, a first upper limiting layer, a mode expansion layer, a second lower limiting layer, a second lower waveguide layer, a second quantum well, a second upper waveguide layer, a second upper limiting layer, a protective layer and a cap layer from bottom to top. The invention also provides a preparation method of the dual-band semiconductor laser device. Two groups of different material systems are simultaneously grown in the same epitaxial structure, so that simultaneous lasing of visible light and near-infrared bands is realized. According to the invention, the carrier limiting capability of the first active region is reduced, the carrier overflow is enhanced, and the lasing of the second active region is realized. The mode expansion layer is arranged between the first active region and the second active region, so that a light field is concentrated, and simultaneous lasing of the first active region and the second active region is facilitated.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and specifically to a dual-band semiconductor laser device and its fabrication method. Background Technology

[0002] Lasers, characterized by their high directionality, strong monochromaticity, and high brightness, have experienced rapid development since the 1960s. They have been integrated with multiple disciplines to form various application technologies, widely used in industrial processing, measurement, communications, defense, and medicine. With the development of airborne optoelectronic systems, laser ranging systems have become an important sensor component. However, due to the complex operating environment, existing products still have certain shortcomings, such as a single detection wavelength, which can easily cause eye damage. Therefore, to meet the needs of practical applications, dual-wavelength output, including near-infrared detection and human eye recognition bands, is required.

[0003] Patent CN120419062A discloses a dual-wavelength laser that forms multiple optically isolated lasers on a single semiconductor wafer by removing a portion of a first laser formed on a first semiconductor layer and using docking coupling technology to form a second laser. This solves the laser integration problem and achieves miniaturization and cost reduction of the device. Although this method can achieve integrated coupling of multiple wavelength lasers, it requires removing a portion from the first structure before docking coupling, which is technically challenging.

[0004] Patent CN114374146B discloses a GaAs-based 915nm / 976nm high-power dual-wavelength laser epitaxial wafer and its fabrication method. This method connects two quantum well epitaxial structures (915nm and 976nm) by constructing a tunnel junction. The dual-wavelength epitaxial structure achieves dual-wavelength excitation on a single epitaxial chip through the tunnel junction connection. However, the tunnel junction requires heavy doping to increase the tunneling probability. High doping concentration easily leads to increased defect density. Simultaneously, the double epitaxial layer structure is relatively thick, and current expansion easily leads to multimode lasing, with the voltage increasing exponentially, equivalent to the sum of the voltages when the two junctions are connected in series.

[0005] Traditional dual-wavelength lasers typically employ multi-fiber coupling or utilize the energy level transition characteristics of fiber optics to achieve three modes of laser output from a single fiber laser, as disclosed in patents such as CN115425508B and CN120093423A. However, these methods suffer from drawbacks such as the difficulty of multi-band fiber coupling and unstable output, hindering the further application of multi-band lasers. Summary of the Invention

[0006] To address the problems of high manufacturing difficulty, difficulty in multi-band fiber coupling, and unstable output in existing dual-band semiconductor laser devices, this invention provides a dual-band semiconductor laser device and its fabrication method to solve the above problems.

[0007] The technical solution of this invention is as follows: In a first aspect, the present invention provides a dual-band semiconductor laser device, comprising, from bottom to top, a GaAs substrate, a GaAs buffer layer, an AlInP first lower confinement layer, and (Al... x1 Ga 1-x1 ) y1 In 1-y1 P first lower waveguide layer, Ga x2 In 1-x2 P first quantum well, (Al) x3 Ga 1-x3 ) y2 In 1-y2 P first upper waveguide layer, Al x4 Ga 1-x4 As the first upper constraint layer, Al x5 Ga 1-x5 As mode extension layer, Al x6 Ga 1-x6 As the second lower confinement layer, Al x7 Ga 1-x7 As the second lower waveguide layer, In x8 Ga 1-x8 As the second quantum well, Al x9 Ga 1-x9 As the second upper waveguide layer, Al x10 Ga 1-x10 As second upper confinement layer, GaAs protective layer, and GaAs cap layer.

[0008] in, (Al x1 Ga 1-x1 ) y1 In 1-y1 In the first lower waveguide layer of P, 0.3≤x1≤0.55, 0.4≤y1≤0.6; Ga x2 In 1-x2 In the first quantum well P, 0.35 ≤ x² ≤ 0.45; (Al x3 Ga 1-x3 ) y2 In 1-y2 In the first upper waveguide layer of P, 0.3≤x3≤0.55, 0.4≤y2≤0.6; Al x4 Ga 1-x4In the first upper constraint layer of As, 0.6 ≤ x4 ≤ 0.8; Al x5 Ga 1-x5 In the As mode extension layer, 0.4 ≤ x5 ≤ 0.5; Al x6 Ga 1-x6 In the second lower constraint layer of As, 0.55≤x6≤0.65; Al x7 Ga 1-x7 In the second lower waveguide layer As, 0.3≤x7≤0.45; In x8 Ga 1-x8 In the second quantum well, 0.05 ≤ x8 ≤ 0.15; Al x9 Ga 1-x9 In the second upper waveguide layer As, 0.3≤x9≤0.45; Al x10 Ga 1-x10 In the second upper constraint layer of As, 0.55≤x10≤0.65.

[0009] Among them, the first quantum well GaInP realizes red light lasing that can be recognized by the human eye, and the second quantum well InGaAs realizes near-infrared lasing; Al x4 Ga 1-x4 As the bandgap difference between the first upper confinement layer and the first quantum well GaInP decreases, the carrier confinement capability is poor, causing some carriers to overflow, thereby realizing lasing in the second active region; Al x5 Ga 1-x5 The As-mode extension layer concentrates the optical field, enabling the optical field to coincide with the quantum well, thus enhancing photoluminescence and lasing capability. The second active region (waveguide layer and quantum well) is doped on the P-side to reduce the doping concentration and absorption loss, which helps to achieve lasing.

[0010] In some embodiments, the doping source of the GaAs buffer layer is Si2H6, and the doping concentration is 2×10⁻⁶. 18 ~5×10 18 atoms / cm 3 The thickness is 0.1~0.3 μm. More preferably, the GaAs buffer layer has a thickness of 0.2 μm and a doping concentration of 2 × 10⁻⁶. 18 atoms / cm 3 .

[0011] In some embodiments, the doping source of the first lower confinement layer of AlInP is Si2H6, and the doping concentration is 5 × 10⁻⁶. 17 ~2×10 18 atoms / cm 3The thickness is 0.5~2μm. More preferably, the thickness of the first lower confinement layer of AlInP is 1.3μm, and the doping concentration is 1.5×10⁻⁶. 18 atoms / cm 3 .

[0012] In some implementations, the (Al) x1 Ga 1-x1 ) y1 In 1-y1 The first lower waveguide layer is unintentionally doped and has a thickness of 20-70 nm. More preferably, x1=0.4, y1=0.5, and a thickness of 35 nm. By employing a low-Al composition waveguide layer and a thin waveguide layer thickness, the carrier confinement capability is reduced, which helps to achieve electron overflow and realize lasing in the second active region.

[0013] In some embodiments, the Ga x2 In 1-x2 The first quantum well of P is unintentionally doped, with a density of 0.35 ≤ x² ≤ 0.45 and a thickness of 5–10 nm. Further preferred is Ga… x2 In 1-x2 The thickness of the first quantum well is 6 nm, x2 = 0.43.

[0014] In some implementations, the (Al) x3 Ga 1-x3 ) y2 In 1-y2 The first upper waveguide layer of P is unintentionally doped, with a thickness of 20-70 nm. More preferably, (Al) x3 Ga 1-x3 ) y2 In 1-y2 The thickness of the first upper waveguide layer is 35 nm, x3 = 0.4, y2 = 0.5. By employing a low-Al composition waveguide layer and a thin waveguide layer thickness, the carrier confinement capability is reduced, which helps to achieve electron overflow and realize the second active region lasing.

[0015] In some implementations, the Al x4 Ga 1-x4 The doping source for the first upper confinement layer is CBr4 or DEZn, with a doping concentration of 7 × 10⁻⁶. 17 ~3×10 18 atoms / cm 3 The thickness is 0.05~0.3μm. More preferably, Al... x4 Ga 1-x4 The thickness of the first upper confinement layer is 0.1 μm, x4 = 0.7, and the doping concentration is 1 × 10⁻⁶. 18 atoms / cm 3 Al x4 Ga1-x4 The use of a low Al composition in the first upper confinement layer reduces carrier confinement capability, which helps to achieve electron overflow and realize lasing in the second active region.

[0016] In some implementations, the Al x5 Ga 1-x5 The doping source for the As-mode extended layer is CBr4 or DEZn (diethylzinc), with a doping concentration of 1×10⁻⁶. 17 ~5×10 17 atoms / cm 3 The thickness is 0.1~0.6μm. More preferably, Al... x5 Ga 1-x5 The thickness of the As-mode extended layer is 0.2 μm, x5 = 0.45, and the doping concentration is 3 × 10⁻⁶. 17 atoms / cm 3 Al x5 Ga 1-x5 The As-mode extended layer has a higher refractive index than the materials on both sides, which concentrates the light field and helps to achieve lasing in the active regions on both sides. At the same time, it uses low doping to reduce absorption loss.

[0017] In some implementations, the Al x6 Ga 1-x6 The doping source for the second lower confinement layer is CBr4 or DEZn, with a doping concentration of 1×10⁻⁶. 17 ~5×10 17 atoms / cm 3 The thickness is 0.1~0.5μm. More preferably, Al... x6 Ga 1-x6 The thickness of the second lower confinement layer is 0.15 μm, x6 = 0.6, and the doping concentration is 3 × 10⁻⁶. 17 atoms / cm 3 Al x6 Ga 1-x6 The second lower confinement layer is lightly doped, which reduces the difficulty of electron migration and helps electrons overflowing from the first active region to reach the second active region for lasing.

[0018] In some implementations, the Al x7 Ga 1-x7 The doping source for the second lower waveguide layer is CBr4 or DEZn, with a doping concentration of 5 × 10⁻⁶. 16 ~2×10 17 atoms / cm 3 The thickness is 20~70nm. Further preferably, Al... x7 Ga 1-x7 The thickness of the second lower waveguide layer is 35 nm, x7 = 0.35, and the doping concentration is 1 × 10⁻⁶. 17atoms / cm 3 Al x7 Ga 1-x7 The second lower waveguide layer is low-doped, which reduces the difficulty of electron migration and helps electrons overflowing from the first active region to reach the second active region for lasing. At the same time, low doping helps reduce absorption loss and realize lasing in the second active region.

[0019] In some implementations, the In x8 Ga 1-x8 The second quantum well is unintentionally doped with As, and has a thickness of 5-10 nm. Further preferably, In... x8 Ga 1-x8 The thickness of the second quantum well is 6 nm, x8 = 0.07. In x8 Ga 1-x8 Undoped second quantum wells reduce absorption losses and facilitate the realization of second active region lasing.

[0020] In some implementations, the Al x9 Ga 1-x9 The doping source for the second upper waveguide layer is CBr4 or DEZn, with a doping concentration of 5 × 10⁻⁶. 16 ~2×10 17 atoms / cm 3 The thickness is 20~70nm. Further preferably, Al... x9 Ga 1-x9 The thickness of the second upper waveguide layer is 35 nm, x9 = 0.35, and the doping concentration is 1 × 10⁻⁶. 17 atoms / cm 3 Al x9 Ga 1-x9 The use of low doping in the second upper waveguide layer helps to reduce absorption loss and realize lasing in the second active region.

[0021] In some implementations, the Al x10 Ga 1-x10 The doping source for the second upper confinement layer is CBr4 or DEZn, with a doping concentration of 5 × 10⁻⁶. 17 ~2×10 18 atoms / cm 3 The thickness is 0.6~1.5μm. More preferably, Al... x10 Ga 1-x10 The thickness of the second upper confinement layer is 0.8 μm, x10 = 0.6, and the doping concentration is 1 × 10⁻⁶. 18 atoms / cm 3 Al x10 Ga 1-x10The second upper confinement layer of As is highly doped, which helps to suppress electron overflow in the second active region and improve lasing efficiency. At the same time, high doping helps to reduce voltage.

[0022] In some embodiments, the doping source of the GaAs protective layer is CBr4 or DEZn, and the doping concentration is 5 × 10⁻⁶. 17 ~2×10 18 atoms / cm 3 The thickness is 10~50 nm. More preferably, the GaAs protective layer has a thickness of 20 nm and a doping concentration of 1×10⁻⁶. 18 atoms / cm 3 .

[0023] In some embodiments, the GaAs cap layer has a thickness of 0.2~0.6 μm, the doping source is CBr4 or DEZn, and the doping concentration is 4×10⁻⁶. 19 ~1×10 20 atoms / cm 3 Further preferably, the thickness is 0.4 μm and the doping concentration is 7 × 10⁻⁶. 19 atoms / cm 3 .

[0024] Secondly, the present invention provides a method for preparing the above-mentioned dual-band semiconductor laser device, comprising the following steps: (1) Place the GaAs substrate in the growth chamber of the MOCVD equipment, heat the H2 environment to 720±10℃ for baking, and introduce AsH3 to perform surface heat treatment on the GaAs substrate. (2) The temperature is slowly reduced to 680±10℃, and the cooling rate is not higher than 30℃ / min. TMGa (trimethylgallium) and AsH3 are continued to be introduced to grow a GaAs buffer layer on the GaAs substrate. The purpose is to prevent defects from spreading from the substrate into the confinement layer, provide a fresh growth interface, and improve the material growth quality. (3) The temperature is maintained at 680±10℃. Growth is stopped on the GaAs buffer layer. PH3 is introduced to stop the growth by stopping the V source (100% AsH3) and the III source (TMGa). The stoppage lasts from 3s to 30s, and the As atoms in the reaction chamber are exhausted. (4) The temperature is maintained at 680±10℃, and TMAl (trimethylaluminum), TMGa, TMIn (trimethylindium) and PH3 are introduced to grow the first lower confinement layer of AlInP on the GaAs buffer layer; (5) The temperature is gradually increased to 630±10℃, and TMAl, TMGa, TMIn and PH3 are introduced to grow AlInP on the first lower confinement layer. x1 Ga 1-x1 ) y1 In1-y1 P First lower waveguide layer; (6) The temperature is maintained at 630±10℃, and TMGa, TMIn and PH3 are introduced into the mixture (Al) x1 Ga 1-x1 ) y1 In 1-y1 Ga is grown on the first lower waveguide layer of P. x2 In 1-x2 P-first quantum well; (7) The temperature is gradually increased to 680±10℃, and TMAl, TMGa, TMIn and PH3 are introduced. x2 In 1-x2 Growth on the first quantum well (Al) x3 Ga 1-x3 ) y2 In 1-y2 P First upper waveguide layer; (8) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced, in (Al x3 Ga 1-x3 ) y2 In 1-y2 Al is grown on the first upper waveguide layer of P. x4 Ga 1-x4 As the first upper constraint layer; (9) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x4 Ga 1-x4 Al is grown on the first upper confinement layer. x5 Ga 1-x5 As mode extension layer; (10) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x5 Ga 1-x5 Al is grown on the As mode extension layer x6 Ga 1-x6 As the second lower constraint layer; (11) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x6 Ga 1-x6 Al is grown on the second lower confinement layer. x7 Ga 1-x7 As the second lower waveguide layer; (12) The temperature is maintained at 680±10℃, and TMGa, TMIn and AsH3 are introduced into Al. x7 Ga 1-x7 In grown on the second lower waveguide layer x8 Ga 1-x8 As the second quantum well; (13) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into In x8 Ga 1-x8 Al growing on the second quantum well x9 Ga 1-x9 As the second upper waveguide layer; (14) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x9 Ga 1-x9 Al is grown on the second upper waveguide layer. x10 Ga 1-x10 As the second upper constraint layer; (15) The temperature was maintained at 680±10℃, and TMGa and AsH3 were introduced into Al. x10 Ga 1-x10 A GaAs protective layer is grown on the second upper confinement layer; (16) Reduce the temperature to 540±10℃, with a cooling rate not exceeding 40℃ / min, and continue to introduce TMGa and AsH3 to grow a GaAs cap layer on the GaAs protective layer.

[0025] TMGa, TMIn, TMAl, PH3, AsH3, etc. are all raw materials for MOCVD (metal-organic chemical vapor deposition) epitaxial growth, while Si2H6, Cp2Mg, CBr4, DEZn, etc. are all doping sources for epitaxial growth.

[0026] The beneficial effects of this invention are as follows: This invention achieves simultaneous lasing in the visible and near-infrared bands by simultaneously growing two different material systems (a first active region and a second active region) in the same epitaxial structure. This invention enhances carrier overflow by reducing the carrier confinement capability of the first active region, thus enabling lasing in the second active region. This invention also facilitates simultaneous lasing of the first and second active regions by placing a mode extension layer between them to concentrate the light field. Furthermore, this invention reduces absorption loss and improves the lasing efficiency of the second active region by using low-doping in the second active region. Finally, this invention utilizes a shared PN junction between two quantum wells to prevent a significant voltage increase during dual-wavelength lasing. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1This is a schematic diagram of the structure of the dual-band semiconductor laser device prepared according to the present invention.

[0029] In the figure, 1-GaAs substrate, 2-GaAs buffer layer, 3-AlInP first lower confinement layer, 4-(Al x1 Ga 1-x1 ) y1 In 1-y1 P first lower waveguide layer, 5-Ga x2 In 1-x2 p-first quantum well, 6-(Al) x3 Ga 1-x3 ) y2 In 1-y2 P first upper waveguide layer, 7-Al x4 Ga 1- x4 As the first upper confinement layer, 8-Al x5 Ga 1-x5 As mode extension layer, 9-Al x6 Ga 1-x6 As the second lower confinement layer, 10-Al x7 Ga 1-x7 As the second lower waveguide layer, 11-In x8 Ga 1-x8 As a second quantum well, 12-Al x9 Ga 1-x9 As the second upper waveguide layer, 13-Al x10 Ga 1-x10 As second upper confinement layer, 14-GaAs protective layer, 15-GaAs cap layer. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0031] Example 1 A method for fabricating the above-mentioned dual-band semiconductor laser device includes the following steps: (1) Place the GaAs substrate in the growth chamber of the MOCVD equipment, heat the H2 environment to 720±10℃ for baking, and introduce AsH3 to perform surface heat treatment on the GaAs substrate. (2) The temperature is slowly reduced to 680±10℃, with a cooling rate not exceeding 30℃ / min. TMGa and AsH3 are continuously introduced to grow a GaAs buffer layer on the GaAs substrate. The doping source of the GaAs buffer layer is Si2H6, and the doping concentration is 2×10⁻⁶. 18 atoms / cm 3 The thickness of the GaAs buffer layer is 0.2 μm; (3) The temperature is maintained at 680±10℃, and the growth of AsH3 and TMGa is stopped. The growth on the GaAs buffer layer is stopped for 20s to exhaust the As atoms in the reaction chamber. (4) The temperature is maintained at 680±10℃, and TMAl, TMGa, TMIn and PH3 are introduced to grow the first lower confinement layer of AlInP on the GaAs buffer layer; the doping source of the first lower confinement layer of AlInP is Si2H6, and the doping concentration is 1.5×10 18 atoms / cm 3 The thickness of the first lower confinement layer of AlInP is 1.3 μm; (5) The temperature is gradually increased to 630±10℃, and TMAl, TMGa, TMIn and PH3 are introduced to unintentionally dope the first lower confinement layer of AlInP, growing a 35nm thick Al(Al) layer. 0.4 Ga 0.6 ) 0.5 In 0.5 P First lower waveguide layer; (6) The temperature is maintained at 630±10℃, and TMGa, TMIn and PH3 are introduced into the mixture (Al) 0.4 Ga 0.6 ) 0.5 In 0.5 Unintentional doping was performed on the first lower waveguide layer of P, and a Ga layer with a thickness of 6 nm was grown. 0.43 In 0.57 P-first quantum well; (7) The temperature is gradually increased to 680±10℃, and TMAl, TMGa, TMIn and PH3 are introduced. 0.43 In 0.57 Unintentional doping was performed on the first quantum well of P, and a 35 nm thick (Al) layer was grown. 0.4 Ga 0.6 ) 0.5 In 0.5 P First upper waveguide layer; (8) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced, in (Al 0.4 Ga 0.6 ) 0.5 In 0.5 An Al layer with a thickness of 0.1 μm is grown on the first upper waveguide layer. 0.7Ga 0.3 As the first upper constraint layer, Al 0.7 Ga 0.3 The doping source for the first upper confinement layer is CBr4, and the doping concentration is 1×10⁻⁶. 18 atoms / cm 3 ; (9) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al 0.7 Ga 0.3 Al with a thickness of 0.2 μm is grown on the first upper confinement layer. 0.45 Ga 0.55 As mode extension layer; Al 0.45 Ga 0.55 The doping source for the As-mode extended layer is CBr4, with a doping concentration of 3 × 10⁻⁶. 17 atoms / cm 3 ; (10) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al 0.45 Ga 0.55 Al with a thickness of 0.15 μm was grown on the As mode extended layer. 0.6 Ga 0.4 As the second lower confinement layer; the doping source for the second lower confinement layer is CBr4, and the doping concentration is 3 × 10⁻⁶. 17 atoms / cm 3 ; (11) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al 0.6 Ga 0.4 Al with a thickness of 35 nm is grown on the second lower confinement layer. 0.35 Ga 0.65 As the second lower waveguide layer; Al 0.35 Ga 0.65 The doping source for the second lower waveguide layer is CBr4, with a doping concentration of 1×10⁻⁶. 17 atoms / cm 3 ; (12) The temperature is maintained at 680±10℃, and TMGa, TMIn and AsH3 are introduced into Al. 0.35 Ga 0.65 Unintentional doping was performed on the second lower waveguide layer, and an In core with a thickness of 6 nm was grown. 0.07 Ga 0.93 As the second quantum well; (13) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into In 0.07 Ga 0.93 Al with a thickness of 35 nm is grown on the second quantum well.0.35 Ga 0.65 As the second upper waveguide layer; the doping source of the second upper waveguide layer is CBr4, and the doping concentration is 1×10⁻⁶. 17 atoms / cm 3 ; (14) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al 0.35 Ga 0.65 An Al layer with a thickness of 0.8 μm is grown on the second upper waveguide layer. 0.6 Ga 0.4 As the second upper confinement layer; the doping source of the second upper confinement layer is CBr4, and the doping concentration is 1×10⁻⁶. 18 atoms / cm 3 ; (15) The temperature was maintained at 680±10℃, and TMGa and AsH3 were introduced into Al. 0.35 Ga 0.65 A 20 nm thick GaAs protective layer is grown on the second upper confinement layer of GaAs; the doping source of the GaAs protective layer is CBr4, and the doping concentration is 1 × 10⁻⁶. 18 atoms / cm 3 ; (16) The temperature was lowered to 540±10℃ at a rate not exceeding 40℃ / min, and TMGa and AsH3 were continuously introduced to grow a GaAs cap layer with a thickness of 0.4μm on the GaAs protective layer. The doping source of the GaAs cap layer was CBr4, and the doping concentration was 7×10⁻⁶. 19 atoms / cm 3 .

[0032] The dual-band semiconductor laser device prepared in Example 1 comprises, from bottom to top, a GaAs substrate, a GaAs buffer layer, an AlInP first lower confinement layer, and (Al... 0.4 Ga 0.6 ) 0.5 In 0.5 P first lower waveguide layer, Ga 0.43 In 0.57 P first quantum well, (Al) 0.4 Ga 0.6 ) 0.5 In 0.5 P first upper waveguide layer, Al 0.7 Ga 0.3 As the first upper constraint layer, Al 0.45 Ga 0.55 As mode extension layer, Al 0.6 Ga 0.4 As the second lower confinement layer, Al 0.35 Ga 0.65 As the second lower waveguide layer, In0.07 Ga 0.93 As the second quantum well, Al 0.35 Ga 0.65 As the second upper waveguide layer, Al 0.6 Ga 0.4 As second upper confinement layer, GaAs protective layer, and GaAs cap layer.

[0033] Test case The dual-band semiconductor laser device prepared in Example 1 was fabricated into a 300×250μm chip, with a stripe width of 3μm and a cavity length of 300μm, and packaged onto a COS heat sink. Meanwhile, Comparative Examples 1 and 2 were fabricated into semiconductor laser devices with a conventional tunnel junction structure according to the method of patent CN114374146B, with Comparative Example 2 having an increased wavelength. Both Comparative Examples 1 and 2 were fabricated into 300×250μm chips, with a stripe width of 3μm and a cavity length of 300μm, and packaged onto a COS heat sink. The samples were tested at room temperature with an operating current of 20mA, and the results are shown in Table 1 below. Table 1 - Test Results

[0034] As can be seen from the results in Table 1, Comparative Example 1, compared to Example 1, uses a traditional tunnel junction structure. While it achieves dual-wavelength lasing with similar threshold voltages, the voltage is almost twice that of Example 1 at the same 20mA current. This is because although Comparative Example 1 uses tunnel cascading, it is essentially still two PN junctions operating in series. Comparative Example 2 still has a higher voltage than Example 1, but it is lower than Comparative Example 1 because the dual wavelengths are longer, mainly due to the influence of its quantum gap. Furthermore, the epitaxial growth thickness of both comparative examples is larger, resulting in a much higher cost than Example 1. The above demonstrates that the dual-band semiconductor laser device prepared by this invention can achieve dual-wavelength lasing at a lower cost and lower voltage.

[0035] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A dual-band semiconductor laser device, characterized in that, The dual-band semiconductor laser device comprises, from bottom to top, a GaAs substrate, a GaAs buffer layer, an AlInP first lower confinement layer, and (Al... x1 Ga 1-x1 ) y1 In 1-y1 P first lower waveguide layer, Ga x2 In 1-x2 P first quantum well, (Al) x3 Ga 1-x3 ) y2 In 1-y2 P first upper waveguide layer, Al x4 Ga 1-x4 As the first upper constraint layer, Al x5 Ga 1-x5 As mode extension layer, Al x6 Ga 1-x6 As the second lower confinement layer, Al x7 Ga 1-x7 As the second lower waveguide layer, In x8 Ga 1-x8 As the second quantum well, Al x9 Ga 1-x9 As the second upper waveguide layer and Al x10 Ga 1-x10 As second upper confinement layer, GaAs protective layer and GaAs cap layer; in, (Al x1 Ga 1-x1 ) y1 In 1-y1 In the first lower waveguide layer of P, 0.3≤x1≤0.55, 0.4≤y1≤0.6; Ga x2 In 1-x2 In the first quantum well P, 0.35 ≤ x² ≤ 0.45; (Al x3 Ga 1-x3 ) y2 In 1-y2 In the first upper waveguide layer of P, 0.3≤x3≤0.55, 0.4≤y2≤0.6; Al x4 Ga 1-x4 In the first upper constraint layer of As, 0.6 ≤ x4 ≤ 0.8; Al x5 Ga 1-x5 In the As mode extension layer, 0.4 ≤ x5 ≤ 0.5; Al x6 Ga 1-x6 In the second lower constraint layer of As, 0.55≤x6≤0.65; Al x7 Ga 1-x7 In the second lower waveguide layer As, 0.3≤x7≤0.45; In x8 Ga 1-x8 In the second quantum well, 0.05 ≤ x8 ≤ 0.15; Al x9 Ga 1-x9 In the second upper waveguide layer As, 0.3≤x9≤0.45; Al x10 Ga 1-x10 In the second upper constraint layer of As, 0.55≤x10≤0.

65.

2. The dual-band semiconductor laser device as described in claim 1, characterized in that, The (Al) x1 Ga 1-x1 ) y1 In 1-y1 The first lower waveguide layer of P is unintentionally doped and has a thickness of 20~70nm.

3. The dual-band semiconductor laser device as described in claim 1, characterized in that, The Ga x2 In 1-x2 The first quantum well of P is unintentionally doped and has a thickness of 5~10 nm.

4. The dual-band semiconductor laser device as described in claim 1, characterized in that, The (Al) x3 Ga 1-x3 ) y2 In 1-y2 The first upper waveguide layer of P is unintentionally doped, with a thickness of 20~70nm.

5. A dual-band semiconductor laser device as described in claim 1, characterized in that, The Al x4 Ga 1-x4 The doping source for the first upper confinement layer is CBr4 or DEZn, with a doping concentration of 7 × 10⁻⁶. 17 ~3×10 18 atoms / cm 3 The thickness is 0.05~0.3μm.

6. A dual-band semiconductor laser device as described in claim 1, characterized in that, The Al x5 Ga 1-x5 The doping source for the As-mode extended layer is CBr4 or DEZn, with a doping concentration of 1×10⁻⁶. 17 ~5×10 17 atoms / cm 3 The thickness is 0.1~0.6μm.

7. A dual-band semiconductor laser device as described in claim 1, characterized in that, The Al x7 Ga 1-x7 The doping source for the second lower waveguide layer is CBr4 or DEZn, with a doping concentration of 5 × 10⁻⁶. 16 ~2×10 17 atoms / cm 3 The thickness is 20~70nm.

8. A dual-band semiconductor laser device as described in claim 1, characterized in that, The In x8 Ga 1-x8 The As second quantum well is unintentionally doped with a thickness of 5~10nm.

9. A dual-band semiconductor laser device as described in claim 1, characterized in that, The Al x9 Ga 1-x9 The doping source for the second upper waveguide layer is CBr4 or DEZn, with a doping concentration of 5 × 10⁻⁶. 16 ~2×10 17 atoms / cm 3 The thickness is 20~70nm.

10. A method for fabricating a dual-band semiconductor laser device as described in claim 1, characterized in that, Includes the following steps: (1) Place the GaAs substrate in the growth chamber of the MOCVD equipment, heat the H2 environment to 720±10℃ for baking, and introduce AsH3 to perform surface heat treatment on the GaAs substrate. (2) The temperature is slowly reduced to 680±10℃, and the cooling rate is not higher than 30℃ / min. TMGa and AsH3 are continued to be introduced to grow a GaAs buffer layer on the GaAs substrate. (3) The temperature is maintained at 680±10℃. Growth is stopped on the GaAs buffer layer. PH3 is introduced to stop the growth by stopping the V and III sources. The stoppage lasts from 3s to 30s, and the As atoms in the reaction chamber are exhausted. (4) The temperature is maintained at 680±10℃, and TMAl, TMGa, TMIn and PH3 are introduced to grow the first lower confinement layer of AlInP on the GaAs buffer layer. (5) The temperature is gradually increased to 630±10℃, and TMAl, TMGa, TMIn and PH3 are introduced to grow AlInP on the first lower confinement layer. x1 Ga 1-x1 ) y1 In 1-y1 P First lower waveguide layer; (6) The temperature is maintained at 630±10℃, and TMGa, TMIn and PH3 are introduced into the mixture (Al) x1 Ga 1-x1 ) y1 In 1-y1 Ga is grown on the first lower waveguide layer of P. x2 In 1-x2 P-first quantum well; (7) The temperature is gradually increased to 680±10℃, and TMAl, TMGa, TMIn and PH3 are introduced. x2 In 1-x2 Growth on the first quantum well (Al) x3 Ga 1-x3 ) y2 In 1-y2 P First upper waveguide layer; (8) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced, in (Al x3 Ga 1-x3 ) y2 In 1-y2 Al is grown on the first upper waveguide layer of P. x4 Ga 1-x4 As the first upper constraint layer; (9) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x4 Ga 1-x4 Al is grown on the first upper confinement layer. x5 Ga 1-x5 As mode extension layer; (10) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x5 Ga 1-x5 Al is grown on the As mode extension layer x6 Ga 1-x6 As the second lower constraint layer; (11) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x6 Ga 1-x6 Al is grown on the second lower confinement layer. x7 Ga 1-x7 As the second lower waveguide layer; (12) The temperature is maintained at 680±10℃, and TMGa, TMIn and AsH3 are introduced into Al x7 Ga 1-x7 In grown on the second lower waveguide layer x8 Ga 1-x8 As the second quantum well; (13) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into In x8 Ga 1-x8 Al growing on the second quantum well x9 Ga 1-x9 As the second upper waveguide layer; (14) The temperature is maintained at 680±10℃, and TMGa, TMAl and AsH3 are introduced into Al x9 Ga 1-x9 Al is grown on the second upper waveguide layer. x10 Ga 1-x10 As the second upper constraint layer; (15) The temperature was maintained at 680±10℃, and TMGa and AsH3 were introduced into Al. x10 Ga 1-x10 A GaAs protective layer is grown on the second upper confinement layer; (16) Reduce the temperature to 540±10℃, with a cooling rate not exceeding 40℃ / min, and continue to introduce TMGa and AsH3 to grow a GaAs cap layer on the GaAs protective layer.

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