A laser and a method of manufacturing the same

Abstract

Embodiments of the application provide a laser and a manufacturing method thereof, and relate to the technical field of semiconductor lasers. The laser comprises a substrate, and a buffer layer, an N confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, a P confinement layer and an ohmic contact layer sequentially grown on the substrate; the P confinement layer is a periodic laminated structure sequentially laminating an AlGaN layer, an InN nanopore layer and a P-type GaN layer arranged in a direction away from the substrate. The manufacturing method comprises the step of sequentially growing the above layers on the substrate. The application can release the stress of the P confinement layer, reduce the dislocation density and improve the hole injection efficiency.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser technology, and more specifically, to a laser and a method for manufacturing the same. Background Technology

[0002] GaN-based lasers have wide applications in displays, lighting, optical communications, and other fields. A typical laser consists of a buffer layer, an N-confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, a P-confinement layer, and an ohmic contact layer grown sequentially on a substrate.

[0003] However, lasers in related technologies generally suffer from the following problems: the P-confinement layer usually uses a single material system, which is prone to stress accumulation during the growth process, leading to epitaxial layer cracking or the generation of high-density dislocations; at the same time, the P-type doping efficiency is low and the hole injection capability is insufficient, affecting the photoelectric conversion efficiency of the device. Summary of the Invention

[0004] The present invention aims to provide a laser and a method for manufacturing the same, which can release the stress accumulated during epitaxial growth, reduce dislocation density, improve hole injection efficiency, and reduce device operating voltage.

[0005] The embodiments of the present invention can be implemented as follows: In a first aspect, the present invention provides a laser, comprising: Substrate; A buffer layer, an N-confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, a P-confinement layer, and an ohmic contact layer are sequentially grown on the substrate. The P-confinement layer includes an AlGaN layer, an InN nanopore layer, and a P-type GaN layer stacked sequentially along a direction away from the substrate, and the AlGaN layer, the InN nanopore layer, and the P-type GaN layer constitute a periodic stacked structure. The active layer is a single quantum well structure, comprising an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer arranged sequentially along a direction away from the substrate. The thickness of the InGaN graded buffer layer is 1 nm to 5 nm, and in the InGaN graded buffer layer, the In composition gradually increases from 3% to 8% to 9% to 12% along the direction away from the substrate; The defect repair layer is made of GaN material with a thickness of 1 nm and a growth temperature of 700℃~760℃. The defect repair layer is located between the InGaN gradient buffer layer and the InGaN low-temperature growth layer. The GaN lattice constant of the defect repair layer is different from that of InGaN to form interlayer lattice perturbation and interrupt the extension of dislocations from the InGaN gradient buffer layer to the InGaN low-temperature growth layer.

[0006] In an optional embodiment, the number of periods in the periodic stacked structure is 1-20; and / or, in the periodic stacked structure, the thickness of a single AlGaN layer and a single P-type GaN layer is 1 nm to 5 nm, respectively.

[0007] In an optional embodiment, the pore density of the InN nanoporous layer is 10. 6 cm - ²~10¹¹ cm - ², the pore size of the InN nanoporous layer is 5 nm to 100 nm; and / or, the thickness of the InN material in the InN nanoporous layer is 0.1 nm to 50 nm.

[0008] In optional embodiments, the substrate is a GaN substrate, a sapphire substrate, or a silicon carbide substrate; and / or, The buffer layer is made of GaN material with a thickness of 20 nm to 2000 nm; and / or, The N-confinement layer is an N-type doped AlGaN or GaN material with a thickness of 100 nm to 1000 nm; and / or, The lower waveguide layer is made of InGaN material with a thickness of 100 nm to 500 nm; and / or, The upper waveguide layer is made of InGaN material with a thickness of 100 nm to 500 nm; and / or, The electron blocking layer is made of AlGaN material, with an Al content of 5% to 30% and a thickness of 5 nm to 100 nm; and / or, The ohmic contact layer is made of p-type doped GaN material with a thickness of 10 nm to 100 nm and a Mg doping concentration of 1 × 10². 0 cm - ³~1×10²¹ cm - ³.

[0009] In an optional embodiment, the thickness of the InGaN low-temperature growth layer is 2 nm to 5 nm, and the In composition of the InGaN low-temperature growth layer is 12% to 25%; and / or, The transition layer is made of InGaN material, and the In content of the transition layer gradually decreases from the InGaN low-temperature grown layer to below 10%; and / or, The barrier layer is made of GaN or AlGaN material and has a thickness of 1 nm to 10 nm.

[0010] Secondly, the present invention provides a method for manufacturing a laser, comprising the following steps: Provide a substrate; A buffer layer, an N-confining layer, and a lower waveguide layer are sequentially grown on the substrate. An active layer is grown on the lower waveguide layer. The growth steps of the active layer include sequentially forming an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer in a direction away from the substrate to form a single quantum well structure. The steps for forming the InGaN gradient buffer layer include: controlling the reaction chamber pressure to 200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMIn as the In source, gradually decreasing the growth temperature from 760℃~850℃ to 700℃~760℃, and simultaneously gradually increasing the amount of In source introduced, so that the In composition gradually increases from 3%~8% to 9%~12% along the direction away from the substrate, and the growth thickness is 1 nm~5 nm; The steps for forming the defect repair layer include: controlling the reaction chamber temperature to 700~760℃ and the pressure to 200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, and growing a GaN defect repair layer with a thickness of 1 nm; the defect repair layer is located between the InGaN graded buffer layer and the InGaN low-temperature growth layer, and the GaN lattice constant of the defect repair layer is different from that of InGaN to form interlayer lattice perturbation and interrupt the extension of dislocations from the InGaN graded buffer layer to the InGaN low-temperature growth layer; A waveguide layer is grown on the active layer; An electron blocking layer is grown on the upper waveguide layer; Growing a P-confinement layer on the electron blocking layer includes a cyclic step of sequentially growing an AlGaN layer, an InN nanopore layer, and a P-type GaN layer, and repeating the cyclic step at least once to form a periodic stacked structure; wherein, the step of growing the InN nanopore layer includes first growing InN material, and then processing nanopores on the InN material. An ohmic contact layer is grown on the P-confined layer.

[0011] In an optional embodiment, the step of providing a substrate includes: controlling the reaction chamber temperature to 1000℃~1200℃ and the pressure to 200 Torr~600 Torr, and performing high-temperature annealing on the substrate for 5min~8min in an H2 atmosphere; The steps for growing the buffer layer include: controlling the reaction chamber temperature to 1050℃~1150℃, the pressure to 200 Torr~400 Torr, introducing NH3 as the N source, N2 and H2 as the carrier gas, introducing TMGa as the Ga source, and growing a GaN buffer layer with a thickness of 20nm~2000nm. The steps for growing the N-confinement layer include: controlling the reaction chamber temperature to 1100℃~1150℃, the pressure to 100 Torr~500 Torr, introducing NH3 as an N source, N2 and H2 as carrier gases, introducing TMGa as a Ga source, TMAl as an Al source, introducing SiH4 as an N-type doping source, and growing an N-type AlGaN layer with a thickness of 100nm~1000nm; The steps for growing the lower waveguide layer include: controlling the temperature of the reaction chamber to 700℃~800℃ and the pressure to 100 Torr~500 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMIn as the In source, and growing an InGaN lower waveguide layer with a thickness of 100nm~500nm. The steps for growing the upper waveguide layer include: controlling the temperature of the reaction chamber to 700℃~800℃ and the pressure to 100 Torr~500 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMI as the In source, and growing an InGaN upper waveguide layer with a thickness of 100nm~500nm. The steps for growing the electron blocking layer include: controlling the reaction chamber temperature to 700℃~800℃, the pressure to 50 Torr~200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMAl as the Al source, and growing an AlGaN electron blocking layer with a thickness of 5nm~100 nm. The steps for growing the ohmic contact layer include: controlling the reaction chamber temperature to 800℃~950℃, the pressure to 100 Torr~400 Torr, introducing NH3 as an N source, introducing TMGa as a Ga source, introducing CP2Mg as a P-type doping source, and the Mg doping concentration to be 1×10². 0 cm - ³~1×10²¹ cm - ³, grow a P-type GaN ohmic contact layer with a thickness of 10 nm to 100 nm.

[0012] In an optional implementation, the step of growing the active layer includes: Low-temperature growth of InGaN layer: The reaction chamber temperature is controlled at 650℃~800℃, the pressure is 200 Torr, N2 is used as carrier gas, NH3 is introduced as N source, TEGa is introduced as Ga source, and TMI is introduced as In source. InGaN material with In content of 12%~25% is grown and the growth thickness is 2 nm~5 nm. Growth transition layer: The reaction chamber pressure is controlled at 200 Torr, N2 is used as the carrier gas, NH3 is introduced as the N source, TEGa is introduced as the Ga source, and TMI is introduced as the In source. The growth temperature is gradually increased from the growth temperature of the InGaN low-temperature growth layer by 20℃~100℃, while the amount of In source introduced is gradually reduced, so that the In composition is gradually reduced from the InGaN low-temperature growth layer to below 10%. Growth barrier layer: The reaction chamber temperature is controlled at 850℃ and the pressure at 200 Torr. A mixture of N2 and H2 is used as the carrier gas, NH3 is introduced as the N source, and TEGa is introduced as the Ga source to grow a GaN barrier layer with a thickness of 1nm~10nm.

[0013] The beneficial effects of the laser and laser manufacturing method provided in the embodiments of the present invention include: The laser and its fabrication method provided in this invention utilize a periodic stacked structure of AlGaN layer, InN nanopore layer, and P-type GaN layer, where the P-confinement layer is configured. This periodic structure's strain compensation effect effectively releases stress between adjacent layers, thereby suppressing epitaxial layer cracking, reducing through-dislocation density, and improving the overall crystal quality of the P-confinement layer. Simultaneously, the InN nanopore layer acts as a stress absorption layer, buffering stress generated during subsequent growth through its porous structure. Furthermore, InN's narrow bandgap allows it to act as a hole accumulation layer, increasing local hole concentration and improving hole injection efficiency. This reduces the device's series resistance and operating voltage, thus minimizing Joule heating. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the laser structure provided in this embodiment; Figure 2 This is a flowchart illustrating the laser fabrication method provided in this embodiment; Figure 3 This is a schematic diagram of the process for growing an active layer on the lower waveguide layer. Figure 4 This is a schematic diagram of the process for growing a P-confinement layer on an electron blocking layer.

[0016] Icons: 100-Laser; 1-Substrate; 2-Buffer layer; 3-N-Confinement layer; 4-Lower waveguide layer; 5-Active layer; 6-Upper waveguide layer; 7-Electron blocking layer; 8-P-Confinement layer; 9-Ohmic contact layer. Detailed Implementation

[0017] Lasers in related technologies typically employ a single AlGaN material system in the p-confinement layer and a multi-quantum-well structure in the active region. However, the p-confinement layer of a single material system is prone to accumulating large stresses during growth, leading to epitaxial layer cracking or the generation of high-density through-dislocations, which affects crystal quality. At the same time, p-type dopants in AlGaN materials have high activation energies and low hole injection efficiency, resulting in high device series resistance, high operating voltage, and severe heat generation.

[0018] To address the aforementioned problems, this invention provides a laser and its fabrication method. By setting the P-confinement layer as a periodic stacked structure of AlGaN layer, InN nanopore layer and P-type GaN layer, the strain compensation effect of the periodic structure is utilized to release stress and reduce dislocation density, and the hole injection efficiency is improved through InN nanopore layer. This improves the problems of poor crystal quality and low hole injection efficiency of the P-confinement layer, thereby enhancing the optical output power and reliability of the device.

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0023] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0024] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0025] In addition, for ease of understanding, the technical terms involved in the embodiments of this invention are explained in detail in the table below: Technical term 1: GaN, gallium nitride, is a III-V compound semiconductor material with a band gap of approximately 3.4 eV. It is widely used in the fabrication of blue and green light-emitting devices and laser devices.

[0026] Technical term 2: AlGaN, aluminum gallium nitride, a ternary compound composed of AlN and GaN, whose chemical formula can be represented as Al x Ga 1-x N. Its band gap increases with increasing Al content, and it is often used as an electron blocking layer and confinement layer material.

[0027] Technical term 3: InGaN, Indium Gallium Nitride, a ternary compound composed of InN and GaN, whose chemical formula can be represented as In Ga 1- In. Its bandgap decreases with increasing In content, making it the primary light-emitting material for GaN-based lasers and LEDs.

[0028] Technical term 4: InN, Indium Nitride, a narrow bandgap semiconductor material with a bandgap of approximately 0.7 eV, used in this invention as the matrix material for forming the nanoporous layer.

[0029] Technical term 5: In composition, refers to the atomic molar percentage of In element in group III elements (In+Ga) in InGaN material, i.e., In / (In+Ga)×100%.

[0030] Technical term 6: Al composition, refers to the atomic molar percentage of Al element in AlGaN material relative to group III elements (Al+Ga), i.e. Al / (Al+Ga)×100%.

[0031] The following detailed description, through embodiments and in conjunction with the accompanying drawings, details the overall structure, working principle, and technical effects of the laser provided by the present invention, as well as the detailed steps, implementation principles, and technical effects of the supporting manufacturing method.

[0032] Please refer to Figure 1 This invention provides a laser 100. This laser 100 can be applied to GaN-based semiconductor lasers in fields such as laser display, laser lighting, optical communication, and materials processing.

[0033] The laser 100 includes a substrate 1, and a buffer layer 2, an N-confinement layer 3, a lower waveguide layer 4, an active layer 5, an upper waveguide layer 6, an electron blocking layer 7, a P-confinement layer 8, and an ohmic contact layer 9 sequentially grown on the substrate 1. The P-confinement layer 8 comprises an AlGaN layer, an InN nanopore layer, and a P-type GaN layer sequentially stacked along a direction away from the substrate 1, and the AlGaN layer, InN nanopore layer, and P-type GaN layer form a periodic stacked structure.

[0034] By setting the P-confined layer 8 as a periodic stacked structure of AlGaN layer, InN nanopore layer and P-type GaN layer stacked sequentially, the strain compensation effect of the periodic structure can be used to effectively release the stress between adjacent layers, thereby suppressing epitaxial layer cracking, reducing through dislocation density and improving the crystal quality of P-confined layer 8.

[0035] Meanwhile, the InN nanoporous layer can serve as a stress absorption layer, buffering the stress generated during subsequent growth through its loose porous structure. On the other hand, the narrow bandgap of InN material can serve as a hole accumulation layer, increasing the local hole concentration, thereby improving hole injection efficiency, reducing the series resistance and operating voltage of the device, and thus reducing Joule heating.

[0036] Furthermore, the active layer 5 is a single quantum well structure, comprising an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer arranged sequentially.

[0037] By setting the active layer 5 as a single quantum well structure, including an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer and a barrier layer arranged sequentially, the gradient structure can reduce lattice mismatch stress, reduce defect density in the active region, and suppress the formation of non-radiative recombination centers. This simplifies the epitaxial structure, shortens the epitaxial growth cycle, and effectively improves optical output power and device reliability.

[0038] Nonradiative recombination centers refer to energy traps formed in the epitaxial layer due to crystal defects such as dislocations and In clusters. When charge carriers recombine at these sites, they do not emit photons but instead convert energy into heat, which reduces luminous efficiency and affects device reliability.

[0039] The following is a detailed description of each layer: Substrate 1 provides a crystallographic template and mechanical support for epitaxial growth. Substrate 1 can be made of different materials as needed; in this embodiment, it is a GaN substrate. In other embodiments, substrate 1 can also be a sapphire substrate or a silicon carbide substrate, etc. Before growth, substrate 1 is typically subjected to high-temperature annealing to clean surface particles and oxides. In this embodiment, the annealing temperature is 1000℃~1200℃, the pressure is 200 Torr~600 Torr, and the high-temperature annealing is carried out for 5 minutes to 8 minutes in a H2 atmosphere.

[0040] Buffer layer 2 is located on substrate 1. Buffer layer 2 is used to alleviate lattice mismatch and differences in thermal expansion coefficients between substrate 1 and subsequent epitaxial layers, reducing stress and dislocations caused by mismatch, and providing a high-quality nucleation surface for subsequent epitaxial growth. Buffer layer 2 can be made of different materials as needed. In this embodiment, buffer layer 2 is made of GaN material with a thickness of approximately 1000 nm. In other embodiments, the thickness of buffer layer 2 can also be 20 nm to 2000 nm.

[0041] The N-confinement layer 3 is located above the buffer layer 2. The N-confinement layer 3 is an N-type doped AlGaN material. It is important to note that N-type doping refers to the doping of a semiconductor material with donor impurities, resulting in a significantly higher electron concentration than hole concentration, leading to electron-dominant conductivity. For example, in this invention, the N-confinement layer 3 uses N-type doped AlGaN or GaN material, with silicon (Si) as the donor dopant and silane (SiH4) as the source material. Si atoms replace the positions of group III atoms (Al or Ga) in the AlGaN or GaN lattice, releasing free electrons and making this layer an electron-rich layer. This allows electrons to be injected into the active layer 5, and together with the P-confinement layer 8, a PN junction is formed, achieving effective carrier injection and optical waveguide confinement.

[0042] The N-confining layer 3 serves two main purposes: first, it confines the injected electrons within the active layer 5, preventing them from leaking across the active layer 5 into the P-confining layer 8; second, it utilizes a lower refractive index to confine the generated photons within the active layer 5, forming an optical waveguide structure, thereby improving the laser's gain efficiency and optical output performance.

[0043] The thickness of the N-confining layer 3 can be set as needed. In this embodiment, the thickness is 200 nm. In other embodiments, the thickness can also be 100 nm to 1000 nm.

[0044] The lower waveguide layer 4 is located above the N-confinement layer 3 and below the active layer 5. The lower waveguide layer 4 reduces optical loss during light propagation and, together with the upper waveguide layer 6, forms an optical waveguide structure, effectively confining photons near the active layer 5. The lower waveguide layer 4 is made of InGaN, and its thickness can be set as needed; in this embodiment, the thickness is 300 nm. In other embodiments, the thickness can be 100 nm to 500 nm.

[0045] The active layer 5 is located above the lower waveguide layer 4 and is the core region for generating optical gain in the laser. The active layer 5 is a single quantum well structure, and from the side closest to the lower waveguide layer 4 upwards, that is, along the direction away from the substrate 1, it successively includes an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer.

[0046] It is important to note that a single quantum well structure refers to a quantum well structure in which the active layer 5 consists of only one potential well layer and two barrier layers on either side. Injected carriers undergo radiative recombination within this single well layer to generate photons. In this invention, the single quantum well structure is not simply a single layer of InGaN, but a composite functional structure composed of five sublayers arranged sequentially. Specifically, it includes: an InGaN gradient buffer layer, located at the bottom, which gradually increases the In content to reduce lattice mismatch stress; a defect repair layer, an extremely thin GaN layer used to block dislocation propagation; an InGaN low-temperature growth layer, which is the main light-emitting region (i.e., the potential well layer) and has a high In content; a transition layer, where the In content gradually decreases, smoothly transitioning to the barrier layer; and a barrier layer, located at the top, made of GaN or AlGaN material (i.e., the barrier layer), used to confine carriers.

[0047] Compared with multi-quantum-well structures, single-quantum-well structures have the following advantages: all injected carriers are concentrated in a single well, resulting in a high carrier concentration, making it easier to achieve population inversion, and a lower threshold current density; at the same time, the structure is simple, the epitaxial growth time is short, and the probability of crystal defects is lower; the active layer 5 is small in volume and has better heat dissipation performance.

[0048] The InGaN gradient buffer layer is made of InGaN material with a thickness of 1 nm to 5 nm, and the In content gradually increases along the direction away from the substrate 1. The main function of the InGaN gradient buffer layer is to make the lattice constant transition smoothly from the barrier layer side to the low-temperature growth layer side, reduce the internal stress of the subsequent low-temperature grown InGaN layer, improve lattice matching, and suppress In clustering.

[0049] The defect repair layer, located above the InGaN gradient buffer layer, is a GaN material grown at low temperatures. Its main function is to interrupt dislocations that may extend due to the continuous growth of InGaN material, repair defects generated during the preceding InGaN gradient buffer layer growth, and reduce the propagation of dislocations into the light-emitting region. The thickness of the defect repair layer is 1 nm.

[0050] The InGaN low-temperature growth layer is located above the defect repair layer. The InGaN low-temperature growth layer is made of InGaN material and is the main light-emitting region in active layer 5. The thickness of the InGaN low-temperature growth layer is 2 nm to 5 nm, and the In content is 12% to 25%.

[0051] The transition layer, located above the InGaN low-temperature growth layer and below the barrier layer, is made of InGaN material. The In composition of the transition layer gradually decreases from that of the InGaN low-temperature growth layer to below 10%. As a transition from the InGaN low-temperature growth layer to the barrier layer, the transition layer increases the lattice matching between the two layers and reduces the defect density at their interface through the gradual change in In composition and growth conditions.

[0052] The barrier layer is located at the top of the active layer 5 and is connected to the transition layer. The barrier layer is made of GaN or AlGaN material. The barrier layer is used to confine charge carriers within the luminescent region. The thickness of the barrier layer is 1 nm to 10 nm.

[0053] The upper waveguide layer 6 is located above the active layer 5. The upper waveguide layer 6 is used to reduce optical loss and, together with the lower waveguide layer 4, constitutes an optical waveguide structure. The upper waveguide layer 6 is made of InGaN, and its thickness can be set as needed; in this embodiment, the thickness is 300 nm. In other embodiments, the thickness can be 100 nm to 500 nm.

[0054] An electron blocking layer 7 is located above the upper waveguide layer 6. The electron blocking layer 7 is made of AlGaN material, and the Al composition can be set as needed. Since the mobility of electrons is much higher than that of holes, electrons easily cross the active layer 5 and enter the P-confining layer 8, causing leakage and reducing luminous efficiency. The function of the electron blocking layer 7 is to utilize its high bandgap to form a barrier to prevent electrons from escaping to the P-confining layer 8, while allowing holes to pass through and enter the active layer 5. In this embodiment, the thickness of the electron blocking layer 7 is 20 nm. In other embodiments, the Al composition of the electron blocking layer 7 can be 5%–30%, and the thickness can be 5 nm–100 nm.

[0055] The P-confinement layer 8 is located above the electron blocking layer 7.

[0056] The function of the P-confining layer 8 corresponds to that of the N-confining layer 3. On the one hand, it injects holes into the active layer 5, and on the other hand, it forms the upper and lower claddings of the optical waveguide together with the N-confining layer 3, confining photons and carriers in the active layer 5.

[0057] Specifically, in this invention, the P-confining layer 8 breaks through the single material system and adopts a periodic stacked structure in which AlGaN layer, InN nanopore layer and P-type GaN layer are stacked in sequence.

[0058] It should be noted that the aforementioned periodic stacked structure refers to a multilayer composite structure formed by stacking two or more different material layers in a predetermined order, with each stacking unit constituting one cycle, and repeating the stacking multiple times along the growth direction. In this invention, the periodic stacked structure specifically refers to the structure adopted by the P-confined layer 8, which consists of an AlGaN layer, an InN nanopore layer, and a P-type GaN layer stacked sequentially, with these three layers constituting one repeating cycle, and repeated stacking in the direction away from the substrate 1, with a cycle number of 1 to 20.

[0059] In this periodic stacked structure, the AlGaN layer is not p-type doped, and its high bandgap width is used to confine charge carriers and optical fields, while avoiding the introduction of resistance due to the high activation energy of Mg in AlGaN. The InN nanopore layer is formed by first growing InN material and then processing it to form nanopores. The narrow bandgap width of InN is used to form a hole accumulation layer, which increases the local hole concentration and plays a role in stress release and dislocation blocking. The p-type GaN layer uses magnesium (Mg) as the acceptor dopant, and the source material is magnesia pyrocene (CP2Mg). Mg atoms replace the positions of Ga atoms in the GaN lattice to form acceptor energy levels and generate free holes, making this layer a hole-rich layer.

[0060] It is understandable that P-type doping refers to the doping of semiconductor materials with acceptor impurities, making the hole concentration in the material significantly higher than the electron concentration, and the conductivity type is mainly hole conduction.

[0061] The aforementioned periodic stacked structure injects holes into the active layer 5, which, together with the N-confinement layer 3, forms a PN junction, thereby achieving effective carrier injection and optical waveguide confinement.

[0062] The ohmic contact layer 9 is located above the p-confinement layer 8. The ohmic contact layer 9 is made of highly p-type doped GaN material. The ohmic contact layer 9 is used to reduce the contact resistance between the p-side electrode and the semiconductor, forming a good ohmic contact, allowing current to be injected into the device efficiently and uniformly. In this embodiment, the thickness of the ohmic contact layer 9 is 50 nm, and the Mg doping concentration is 1 × 10². 0 cm - ³~1×10²¹cm - ³. In other embodiments, the thickness of the ohmic contact layer 9 may also be 10 nm to 100 nm.

[0063] It should be noted that the specific materials and thicknesses of the buffer layer 2, N-confining layer 3, lower waveguide layer 4, upper waveguide layer 6, electron blocking layer 7, and ohmic contact layer 9 in the above-mentioned layer structure can be adjusted according to the device design requirements, and are not limited to the specific values ​​given in this embodiment.

[0064] In this embodiment, the number of periods in the periodic stacked structure of the P-confinement layer 8 is 1 to 20. That is, the three layers—AlGaN layer, InN nanopore layer, and P-type GaN layer—form a repeating unit of a period, which is stacked 1 to 20 times. The number of periods can be selected according to the required total thickness of the P-confinement layer 8 and the hole injection efficiency. When the number of periods is small, the total thickness of the P-confinement layer 8 is thinner, and the optical confinement effect is relatively weaker; when the number of periods is large, the total thickness of the P-confinement layer 8 is larger, the optical confinement effect is enhanced, but the growth time is correspondingly extended. A good balance can be achieved between the optical confinement effect and the growth efficiency when the number of periods is in the range of 1 to 20.

[0065] In this embodiment, the pore density of the InN nanopore layer is 10. 6 cm - 2~10¹¹cm - ², the pore size is 5 nm to 100 nm. The formation process of the InN nanoporous layer is as follows: first, InN material is grown, and then etching is performed using an H2 atmosphere to form nanopores. During this process, H2 etches certain areas of the InN material, causing localized removal of the InN material, thereby forming uniformly distributed nanoscale pores.

[0066] It is important to note that the pore density and pore size have a significant impact on device performance. When the pore size is too large, the subsequently grown P-type GaN layer is difficult to fill the pores, or it may produce more defects; when the pore size is too small, the stress relief effect and hole accumulation effect of the pore layer are weak. Controlling the pore size within the range of 5nm to 100nm can balance the pore filling quality and functional performance. A pore density of 10-1 is also beneficial. 6 cm - 2~10¹¹cm - Within a certain range, uniformity of pore distribution and sufficient hole accumulation effect can be guaranteed. The aforementioned pore density and pore size can be achieved by adjusting the growth conditions of the InN material and the H2 etching process parameters.

[0067] In this embodiment, the thickness of the InN material in the InN nanoporous layer is 0.1 nm to 50 nm. The InN material is the initial deposition layer during the growth of the InN nanoporous layer, with a growth temperature of 600℃ to 800℃ and a pressure of 100 Torr to 400 Torr. Within this temperature range, the InN material can grow with high crystal quality, providing a good foundation for subsequent pore formation. The thickness of the InN material determines the thickness of the pore layer. When the InN material thickness is less than 0.1 nm, the formed pore size is too small, limiting the effect on stress release and vacuole accumulation; when the thickness is greater than 50 nm, the overall pore layer is too thick, potentially affecting the overall stress and conductivity of the periodic structure. Therefore, controlling the InN material thickness within the range of 0.1 nm to 50 nm is more suitable.

[0068] In this embodiment, in each cycle of the p-confinement layer 8, the thickness of the monolayer AlGaN is 1 nm to 5 nm, and the thickness of the monolayer p-type GaN is 1 nm to 5 nm. The growth temperature of the AlGaN layer is 900℃ to 1050℃, and the pressure is 50 Torr to 200 Torr. Lower pressure is beneficial for the incorporation of Al elements, ensuring the composition and quality of the AlGaN material. The growth temperature of the p-type GaN layer is 900℃ to 1050℃, and the pressure is 400 Torr to 600 Torr. Higher pressure is beneficial for the activation of p-type dopants and can also improve lattice quality. Controlling the thickness of the AlGaN layer and the p-type GaN layer within the range of 1 nm to 5 nm can ensure the carrier confinement and hole injection effects while avoiding stress accumulation caused by excessively thick monolayers.

[0069] Specifically, the thickness of the InGaN graded buffer layer is 1 nm to 5 nm. In the InGaN graded buffer layer, the In content gradually increases along the growth direction away from the substrate 1, i.e., from bottom to top. Specifically, the In content gradually increases from 3% to 8% to 9% to 12%. Correspondingly, during the growth of the InGaN graded buffer layer, the temperature gradually decreases from 760℃ to 850℃ to 700℃ to 760℃, while the In source injection gradually increases.

[0070] The gradient design, with the In composition gradually increasing from a lower to a higher value, ensures that the lattice constant of the InGaN gradient buffer layer is closer to that of the underlying material on the side near the lower waveguide layer 4, while gradually transitioning to a lattice constant closer to that of the subsequent low-temperature InGaN growth layer on the side near the defect repair layer. This gradient distribution of In composition and lattice constant effectively reduces the lattice mismatch stress between the subsequent low-temperature InGaN layer and the underlying material, suppressing the enrichment and precipitation of In elements at the interface to form clusters, thereby reducing the probability of non-radiative recombination center formation and improving the luminescence efficiency of the active layer 5.

[0071] In this embodiment, the thickness of the InGaN low-temperature grown layer is 2 nm to 5 nm, and the In composition is 12% to 25%. The InGaN low-temperature grown layer is the main light-emitting region of the active layer 5. The higher In composition results in a smaller bandgap, corresponding to a longer emission wavelength. The growth temperature is 650℃ to 800℃. Since the ionization energy of the In-N bond is low, In is easily desorbed at higher temperatures. Therefore, the InGaN low-temperature grown layer is grown at a relatively low temperature, which is conducive to the incorporation of In and ensures the realization of the target In composition.

[0072] The defect repair layer is made of GaN material, with a thickness of 1 nm, and is grown at a temperature of 700℃~760℃. The defect repair layer is inserted between the InGaN graded buffer layer and the InGaN low-temperature growth layer. During the growth of the InGaN graded buffer layer, certain crystal defects may be generated due to changes in the In composition and temperature. The defect repair layer uses low-temperature GaN material. GaN's lattice constant differs from that of InGaN, allowing for interlayer lattice perturbations that disrupt dislocation continuity and prevent dislocations from extending from the InGaN graded buffer layer to the InGaN low-temperature growth layer. Because the defect repair layer is extremely thin, it has minimal impact on the overall band structure and emission wavelength of the quantum well, but it effectively improves the crystal quality of the emitting region.

[0073] The transition layer is made of InGaN, with its In content gradually decreasing from 12%–25% in the low-temperature InGaN growth layer to below 10%. The growth temperature of the transition layer gradually increases from 20°C to 100°C in the low-temperature InGaN growth layer. Located between the low-temperature InGaN growth layer and the barrier layer, this design of gradually decreasing In content and gradually increasing growth temperature allows for a smooth transition of the lattice constant from the high-In-content low-temperature growth layer to the low-In-content or In-free barrier layer. This reduces lattice mismatch at the interface and lowers the interface defect density, thereby improving the overall crystal quality and luminous efficiency of the quantum well.

[0074] The barrier layer is made of GaN or AlGaN material, with a thickness ranging from 1 nm to 10 nm. When AlGaN is used as the barrier layer, its higher bandgap provides stronger carrier confinement, but it may also introduce greater lattice mismatch stress. The material of the barrier layer can be selected between GaN and AlGaN depending on the device design requirements.

[0075] Please refer to Figures 2-4 This invention also provides a method for manufacturing a laser 100, used to prepare the laser 100 described in the above embodiments. The method includes the following steps: S1. A substrate 1 is provided. In this embodiment, substrate 1 is a GaN substrate. First, the reaction chamber temperature is controlled at 1000℃~1200℃, and the reaction chamber pressure is controlled at 200 Torr~600 Torr. The substrate 1 is subjected to high-temperature annealing for 5 minutes to 8 minutes in an H2 atmosphere to clean the particles and oxides on the surface of substrate 1. In this embodiment, the annealing time is 6 minutes.

[0076] S2. Buffer layer 2, N-confining layer 3, and lower waveguide layer 4 are grown sequentially on substrate 1.

[0077] Specifically, a buffer layer 2, which is made of GaN material, is grown on substrate 1. The reaction chamber temperature is controlled at 1050℃~1150℃, the reaction chamber pressure is controlled at 200 Torr~400 Torr, NH3 is introduced as the N source, N2 and H2 are introduced as the carrier gas, and TMGa is introduced as the Ga source to grow a GaN buffer layer 2 with a thickness of 1000nm.

[0078] An N-confinement layer 3, composed of N-type doped AlGaN material, is grown on buffer layer 2. The reaction chamber temperature is controlled at 1100℃~1150℃, the pressure at 100 Torr~500 Torr, NH3 is introduced as the N source, N2 and H2 as carrier gases, TMGa is introduced as the Ga source, TMAl as the Al source, and SiH4 is introduced as the N-type doping source to grow an N-type AlGaN layer with a thickness of 200 nm.

[0079] A lower waveguide layer 4, made of InGaN material, is grown on the N-confined layer 3. The reaction chamber temperature is controlled at 700℃~800℃, the pressure at 100 Torr~500 Torr, the carrier gas is N2, H2 is shut off, NH3 provides the N source, TEGa is introduced as the Ga source, and TMI is introduced as the In source to grow the lower waveguide layer 4 with a thickness of 300nm.

[0080] S3. An active layer 5 is grown on the lower waveguide layer 4. The active layer 5 is a single quantum well, and the growth steps include sequentially forming an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer.

[0081] Specifically, this includes: S301, growing an InGaN gradient buffer layer: the pressure is 200 Torr, the carrier gas is N2, H2 is shut off, NH3 provides the N source, TEGa is introduced as the Ga source, and TMI is introduced as the In source. The growth temperature is gradually decreased from 850℃ to 760℃, the TMI flow rate is gradually increased from 200 sccm to 1500 sccm, and the growth thickness is 3 nm.

[0082] In step S301 above, i.e., the step of growing the InGaN graded buffer layer, the temperature is gradually decreased from 760℃~850℃ to 700℃~760℃, while the In source flux is gradually increased, so that the In composition gradually increases from 3%~8% to 9%~12%. The gradual decrease in temperature is beneficial for the incorporation of In because the ionization energy of the In-N bond is low, and In is less likely to desorb at lower temperatures; the gradual increase in the In source flux directly increases the supply ratio of In source in the gas phase. The coordinated adjustment of temperature and In source flux achieves precise gradual control of the In composition from a lower to a higher value.

[0083] S302, growth defect repair layer.

[0084] In step S302 above, the step of growing the defect repair layer includes growing a GaN material with a thickness of 1 nm at 700℃~760℃. The defect repair layer is grown at a low temperature, ensuring its growth temperature is consistent with that of the upper and lower InGaN layers, thus reducing the impact of temperature fluctuations on crystal quality. The extremely thin thickness allows the defect repair layer to effectively block dislocation propagation without significantly affecting the band structure and luminescence properties of the quantum well.

[0085] S303, Growth of InGaN low-temperature growth layer: pressure is 200 Torr, carrier gas is N2, H2 is off, NH3 provides N source, TEGa is introduced as Ga source, TMI is introduced as In source, growth temperature is 720℃, and growth thickness is 3nm.

[0086] S304, Growth Transition Layer: Pressure 200 Torr, carrier gas N2, H2 shut off, NH3 provides N source, TEGa is introduced as Ga source, and TMI is introduced as In source. Growth temperature gradually increases from 720℃ to 800℃, TMI flow rate gradually decreases from 1500 sccm to 200 sccm, and growth thickness is 0.5 nm.

[0087] S305, Growth Barrier Layer: The growth temperature is 850℃, the pressure is 200Torr, the carrier gas is a mixture of N2 and H2, NH3 provides the N source, and TEGa is introduced as the Ga source to grow a GaN barrier layer with a thickness of 5nm.

[0088] S4. Grow waveguide layer 6 on active layer 5.

[0089] Specifically, the upper waveguide layer 6 is made of InGaN material. The reaction chamber temperature is controlled at 700℃~800℃, the pressure at 100Torr~500Torr, the carrier gas is N2, H2 is shut off, NH3 provides the N source, TEGa is introduced as the Ga source, and TMI is introduced as the In source. The growth thickness is 300nm.

[0090] S5. An electron blocking layer 7 is grown on the upper waveguide layer 6.

[0091] Specifically, electron blocking layer 7 is made of AlGaN material. The reaction chamber temperature is controlled at 700–800℃, the pressure at 50–200 Torr, the carrier gas is N2, H2 is shut off, NH3 provides the N source, TEGa is introduced as the Ga source, and TMAl is introduced as the Al source. The growth thickness is 20 nm.

[0092] S6. A P-confinement layer 8 is grown on the electron blocking layer 7. The P-confinement layer 8 is a periodic stacked structure consisting of an AlGaN layer, an InN nanoporous layer, and a P-type GaN layer stacked sequentially.

[0093] Specifically, this includes: S601, growing AlGaN layers: growth temperature is 900℃~1050℃, and pressure is 50 Torr~200 Torr.

[0094] S602. Forming an InN nanoporous layer: First, InN material is grown, and then nanopores are formed through processing. In this embodiment, InN material with a thickness of 5nm to 50nm is grown first at a growth temperature of 600℃ to 800℃ and a pressure of 100 Torr to 400 Torr. Then, the InN material is etched using an H2 atmosphere to form an InN nanoporous layer.

[0095] S603, growth of P-type GaN layer: growth temperature is 900℃~1050℃, pressure is 400 Torr~600 Torr.

[0096] The growth of AlGaN layer, InN nanoporous layer and P-type GaN layer in the order of S601-S603 is considered as one cycle step, and the cycle step is repeated at least once. In this embodiment, the cycle step is repeated 1 to 20 times.

[0097] S7. An ohmic contact layer 9 is grown on the P-confined layer 8.

[0098] Specifically, the ohmic contact layer 9 is made of highly p-doped GaN material. The growth temperature is 800℃~950℃, the growth pressure is 100 Torr~400 Torr, NH3 is introduced as the N source, TMGa is introduced as the Ga source, and CP2Mg is introduced as the p-type doping source. The Mg doping concentration is 1×10². 0 cm - ³~1×10²¹cm - ³, with a growth thickness of 50 nm.

[0099] By employing the above-described fabrication method, a laser 100 with high crystal quality and good hole injection efficiency can be fabricated by using a single quantum well active layer 5 growth process that includes an InGaN gradient buffer layer, a defect repair layer, a transition layer and a barrier layer, and a periodic growth process that includes a P-confined layer 8 formed by InN nanopores. This can improve the optical output power and reliability of the device.

[0100] In summary, the laser 100 and its fabrication method provided in this embodiment of the invention effectively release stress, reduce dislocation density, and improve hole injection efficiency by setting the P-confining layer 8 as a periodic stacked structure of AlGaN layer, InN nanopore layer, and P-type GaN layer in sequence; and by setting the active layer 5 as a single quantum well structure including InGaN gradient buffer layer, defect repair layer, InGaN low-temperature growth layer, transition layer, and barrier layer, interface defects are reduced and nonradiative recombination is suppressed. Therefore, the optical output power and long-term operational reliability of the device can be significantly improved, while the threshold current and operating voltage are reduced.

[0101] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A laser, characterized in that, include: Substrate; A buffer layer, an N-confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, a P-confinement layer, and an ohmic contact layer are sequentially grown on the substrate. The P-confinement layer includes an AlGaN layer, an InN nanopore layer, and a P-type GaN layer stacked sequentially along a direction away from the substrate, and the AlGaN layer, the InN nanopore layer, and the P-type GaN layer constitute a periodic stacked structure. The active layer is a single quantum well structure, comprising an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer arranged sequentially along a direction away from the substrate. The thickness of the InGaN graded buffer layer is 1 nm to 5 nm, and in the InGaN graded buffer layer, the In composition gradually increases from 3% to 8% to 9% to 12% along the direction away from the substrate; The defect repair layer is made of GaN material with a thickness of 1 nm and a growth temperature of 700℃~760℃. The defect repair layer is located between the InGaN gradient buffer layer and the InGaN low-temperature growth layer. The GaN lattice constant of the defect repair layer is different from that of InGaN to form interlayer lattice perturbation and interrupt the extension of dislocations from the InGaN gradient buffer layer to the InGaN low-temperature growth layer.

2. The laser according to claim 1, characterized in that, The periodic stacked structure has 1-20 periods; and / or, in the periodic stacked structure, the thickness of a single AlGaN layer and a single P-type GaN layer is 1 nm to 5 nm, respectively.

3. The laser according to claim 1, characterized in that, The pore density of the InN nanoporous layer is 10. 6 cm - ²~10¹¹cm - ², the pore size of the InN nanoporous layer is 5 nm to 100 nm; and / or, the thickness of the InN material in the InN nanoporous layer is 0.1 nm to 50 nm.

4. The laser according to claim 1, characterized in that, The substrate is a GaN substrate, a sapphire substrate, or a silicon carbide substrate; and / or, The buffer layer is made of GaN material with a thickness of 20 nm to 2000 nm; and / or, The N-confinement layer is an N-type doped AlGaN or GaN material with a thickness of 100 nm to 1000 nm; and / or, The lower waveguide layer is made of InGaN material with a thickness of 100 nm to 500 nm; and / or, The upper waveguide layer is made of InGaN material with a thickness of 100 nm to 500 nm; and / or, The electron blocking layer is made of AlGaN material, with an Al content of 5% to 30% and a thickness of 5 nm to 100 nm; and / or, The ohmic contact layer is made of p-type doped GaN material with a thickness of 10 nm to 100 nm and a Mg doping concentration of 1 × 10². 0 cm - ³~1×10²¹ cm - ³.

5. The laser according to claim 1, characterized in that, The thickness of the InGaN low-temperature growth layer is 2 nm to 5 nm, and the In composition of the InGaN low-temperature growth layer is 12% to 25%; and / or, The transition layer is made of InGaN material, and the In content of the transition layer gradually decreases from the InGaN low-temperature grown layer to below 10%; and / or, The barrier layer is made of GaN or AlGaN material and has a thickness of 1 nm to 10 nm.

6. A method for manufacturing a laser, characterized in that, Includes the following steps: Provide a substrate; A buffer layer, an N-confining layer, and a lower waveguide layer are sequentially grown on the substrate. An active layer is grown on the lower waveguide layer. The growth steps of the active layer include sequentially forming an InGaN gradient buffer layer, a defect repair layer, an InGaN low-temperature growth layer, a transition layer, and a barrier layer in a direction away from the substrate to form a single quantum well structure. The steps for forming the InGaN gradient buffer layer include: controlling the reaction chamber pressure to 200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMIn as the In source, gradually decreasing the growth temperature from 760℃~850℃ to 700℃~760℃, and simultaneously gradually increasing the amount of In source introduced, so that the In composition gradually increases from 3%~8% to 9%~12% along the direction away from the substrate, and the growth thickness is 1 nm~5 nm; The steps for forming the defect repair layer include: controlling the reaction chamber temperature to 700~760℃ and the pressure to 200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, and growing a GaN defect repair layer with a thickness of 1 nm; the defect repair layer is located between the InGaN graded buffer layer and the InGaN low-temperature growth layer, and the GaN lattice constant of the defect repair layer is different from that of InGaN to form interlayer lattice perturbation and interrupt the extension of dislocations from the InGaN graded buffer layer to the InGaN low-temperature growth layer; A waveguide layer is grown on the active layer; An electron blocking layer is grown on the upper waveguide layer; Growing a P-confinement layer on the electron blocking layer includes a cyclic step of sequentially growing an AlGaN layer, an InN nanopore layer, and a P-type GaN layer, and repeating the cyclic step at least once to form a periodic stacked structure; wherein, the step of growing the InN nanopore layer includes first growing InN material, and then processing nanopores on the InN material. An ohmic contact layer is grown on the P-confined layer.

7. The method for manufacturing a laser according to claim 6, characterized in that, The step of providing a substrate includes: controlling the reaction chamber temperature to 1000℃~1200℃ and the pressure to 200 Torr~600 Torr, and performing high-temperature annealing on the substrate for 5min~8min in H2 atmosphere; The steps for growing the buffer layer include: controlling the reaction chamber temperature to 1050℃~1150℃, the pressure to 200 Torr~400 Torr, introducing NH3 as the N source, N2 and H2 as the carrier gas, introducing TMGa as the Ga source, and growing a GaN buffer layer with a thickness of 20 nm~2000 nm. The steps for growing the N-confinement layer include: controlling the reaction chamber temperature to 1100℃~1150℃, the pressure to 100 Torr~500 Torr, introducing NH3 as an N source, N2 and H2 as carrier gases, introducing TMGa as a Ga source, TMAl as an Al source, introducing SiH4 as an N-type doping source, and growing an N-type AlGaN layer with a thickness of 100 nm~1000 nm; The steps for growing the lower waveguide layer include: controlling the temperature of the reaction chamber to 700℃~800℃ and the pressure to 100 Torr~500 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMIn as the In source, and growing an InGaN lower waveguide layer with a thickness of 100nm~500nm. The steps for growing the upper waveguide layer include: controlling the temperature of the reaction chamber to 700℃~800℃ and the pressure to 100 Torr~500 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMIn as the In source, and growing an InGaN upper waveguide layer with a thickness of 100 nm~500 nm. The steps for growing the electron blocking layer include: controlling the reaction chamber temperature to 700℃~800℃, the pressure to 50 Torr~200 Torr, using N2 as the carrier gas, introducing NH3 as the N source, introducing TEGa as the Ga source, introducing TMAl as the Al source, and growing an AlGaN electron blocking layer with a thickness of 5nm~100 nm. The steps for growing the ohmic contact layer include: controlling the reaction chamber temperature to 800℃~950℃, the pressure to 100 Torr~400 Torr, introducing NH3 as an N source, introducing TMGa as a Ga source, introducing CP2Mg as a P-type doping source, and the Mg doping concentration to be 1×10². 0 cm - ³~1×10²¹ cm - ³, grow a P-type GaN ohmic contact layer with a thickness of 10 nm to 100 nm.

8. The method for manufacturing a laser according to claim 6, characterized in that, The steps for growing the active layer include: Low-temperature growth of InGaN layer: The reaction chamber temperature is controlled at 650℃~800℃, the pressure is 200 Torr, N2 is used as carrier gas, NH3 is introduced as N source, TEGa is introduced as Ga source, and TMI is introduced as In source. InGaN material with In content of 12%~25% is grown and the growth thickness is 2 nm~5 nm. Growth transition layer: The reaction chamber pressure is controlled at 200 Torr, N2 is used as the carrier gas, NH3 is introduced as the N source, TEGa is introduced as the Ga source, and TMI is introduced as the In source. The growth temperature is gradually increased from the growth temperature of the InGaN low-temperature growth layer by 20℃~100℃, while the amount of In source introduced is gradually reduced, so that the In composition is gradually reduced from the InGaN low-temperature growth layer to below 10%. Growth barrier layer: The reaction chamber temperature is controlled at 850℃ and the pressure at 200 Torr. A mixture of N2 and H2 is used as the carrier gas, NH3 is introduced as the N source, and TEGa is introduced as the Ga source to grow a GaN barrier layer with a thickness of 1nm~10nm.

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