Preparation method of semiconductor laser
By distinguishing the suppression layer and dielectric layer on the quantum well epitaxial chip and induced quantum well hybridization by using laser beams, the problem of low optical catastrophic damage threshold for quantum well semiconductor lasers is solved, and precise quantum well hybridization and performance improvement for specific regions is achieved.
Patent Information
- Application Number
- CN202510369022.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2025-07-01
Smart Images
Figure CN120237531A_ABST
Abstract
Description
Technical Field
[0001] This application relates to, but is not limited to, the field of semiconductor laser technology, and particularly relates to a method for fabricating a semiconductor laser. Background Art
[0002] Quantum well semiconductor lasers have extensive applications in many fields such as optical communication, optical storage, and laser processing. However, quantum well semiconductor lasers have the problem of a relatively low optical catastrophic damage threshold, and quantum well intermixing technology is an important means to improve the performance of quantum well semiconductor lasers.
[0003] The quantum well intermixing methods in related technologies have problems of complex processes and difficulty in precisely controlling the impurity diffusion region. Summary of the Invention
[0004] The method for fabricating a semiconductor laser provided by this application can precisely induce quantum well intermixing in a specific region on a quantum well epitaxial wafer.
[0005] This application provides a method for fabricating a semiconductor laser. The method for fabricating the semiconductor laser includes: fabricating a quantum well epitaxial wafer; fabricating an inhibition layer in a first region on a preset surface of the quantum well epitaxial wafer, and fabricating a dielectric layer in a second region on the preset surface; irradiating the second region with a laser beam, where the inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; and the dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer.
[0006] In the method for fabricating a semiconductor laser provided by this application, since the first region and the second region are distinguished on the preset surface of the quantum well epitaxial wafer, an inhibition layer that can inhibit the effect of the laser beam on the quantum well epitaxial wafer is fabricated in the first region, and a dielectric layer that can promote the effect of the laser beam on the quantum well epitaxial wafer is fabricated in the second region. When the preset surface of the quantum well epitaxial wafer is irradiated with the laser beam, the quantum well epitaxial wafer in the first region where the inhibition layer is fabricated will not undergo intermixing or structural change, while the quantum well epitaxial wafer in the second region where the fabricated dielectric layer is located will undergo quantum well intermixing or structural change under the promotion of the dielectric layer. Therefore, the method for fabricating a semiconductor laser according to the embodiments of this application can precisely induce quantum well intermixing in a specific region (the second region) on the quantum well epitaxial wafer.
[0007] In a possible implementation manner of this application, in the step of fabricating an inhibition layer in a first region on a preset surface of the quantum well epitaxial wafer and fabricating a dielectric layer in a second region on the preset surface, it includes: fabricating a prefabricated layer of a first type of material on the preset surface; retaining the prefabricated layer in the first region to form an inhibition layer; removing the prefabricated layer in the second region to form a vacant region; and fabricating a second type of material in the vacant region to form a dielectric layer.
[0008] In a possible implementation manner of the present application, in the step of forming an inhibition layer by retaining the prefabricated layer in the first region and forming a vacant region by removing the prefabricated layer in the second region, it includes: determining the position parameter and size parameter of the second region based on preset performance parameters; etching the first type of material corresponding to the second region based on the position parameter and size parameter to form a vacant region.
[0009] In a possible implementation manner of the present application, before the step of forming an inhibition layer by retaining the prefabricated layer in the first region and forming a vacant region by removing the prefabricated layer in the second region, the manufacturing method of the semiconductor laser further includes: laying a protective layer on the surface of the prefabricated layer, and the protective layer covers at least the first region. After the step of preparing a second type of material in the vacant region to form a dielectric layer, the manufacturing method of the semiconductor laser further includes: removing the protective layer and the second type of material attached thereto.
[0010] In a possible implementation manner of the present application, the second type of material includes Si and SiO2. In the step of preparing a second type of material in the vacant region to form a dielectric layer, it includes: preparing a first SiO2 layer on a preset surface corresponding to the second region; preparing a Si layer on the surface of the first SiO2 layer; preparing a second SiO2 layer on the surface of the Si layer.
[0011] In a possible implementation manner of the present application, the first type of material includes SiO2 and TiO2. In the step of preparing a first type of material on a preset surface to form a prefabricated layer, it includes: preparing a third SiO2 layer on a preset surface corresponding to the first region; preparing a TiO2 layer on the surface of the third SiO2 layer.
[0012] In a possible implementation manner of the present application, the manufacturing method of the semiconductor laser includes: isolating a first region and a second region on a preset surface through an isolation structure; laying a first material in the first region to form an inhibition layer, and laying a second material in the second region to form a dielectric layer.
[0013] In a possible implementation manner of the present application, in the step of irradiating the second region with a laser beam, the inhibition layer is configured to limit the action of the laser beam on the quantum well epitaxial wafer; the dielectric layer is configured to promote the action of the laser beam on the quantum well epitaxial wafer, and it includes: adjusting the parameters of the laser beam based on preset parameters and the characteristic parameters of the second region; irradiating the second region with the adjusted laser beam; wherein, the preset parameters at least include the depth and range of quantum well diffusion; the characteristic parameters at least include the shape parameter of the second region; the laser beam parameters at least include: the shape parameter, size parameter, power parameter, and wavelength parameter of the laser beam.
[0014] In a possible implementation manner of the present application, in the step of irradiating a second region with a laser beam, where the suppression layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; and the dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer, it further includes: monitoring the temperature and optical properties of the second region irradiated by the laser beam; and adjusting the parameters of the laser beam based on the monitoring results.
[0015] In a possible implementation manner of the present application, in the step of irradiating a second region with a laser beam, where the suppression layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; and the dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer, it further includes: annealing the second region after the laser beam irradiation; removing the suppression layer of the first region and removing the dielectric layer of the second region. Description of the Drawings
[0016] Figure 1 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0017] Figure 2 Schematic diagram of the hybrid region of the front and rear cavity surfaces of the semiconductor laser provided by an embodiment of the present application;
[0018] Figure 3 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0019] Figure 4 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0020] Figure 5 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0021] Figure 6 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0022] Figure 7 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0023] Figure 8 Cross-sectional view of the suppression layer and the dielectric layer of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0024] Figure 9 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0025] Figure 10 One of the step diagrams of the method for manufacturing a semiconductor laser provided by an embodiment of the present application;
[0026] Figure 11Schematic diagram of the laser beam irradiating the second region in the method for preparing a semiconductor laser provided by an embodiment of the present application;
[0027] Figure 12 Schematic diagram of the principle of quantum well intermixing in the second region in the method for preparing a semiconductor laser provided by an embodiment of the present application.
[0028] Reference numerals:
[0029] 1 - Quantum well epitaxial wafer; 11 - First region; 12 - Second region; 2 - Semiconductor laser; 21 - Cavity surface; 22 - Resonant cavity; 3 - Inhibiting layer; 31 - Third SiO2 layer; 32 - TiO2 layer; 4 - Dielectric layer; 41 - First SiO2 layer; 42 - Si layer; 43 - Second SiO2 layer; 5 - High-power pulsed laser; 51 - Laser beam. Detailed implementation manners
[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will further describe the specific technical solutions of the present application in detail with reference to the accompanying drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not used to limit the scope of the present application.
[0031] In the embodiments of the present application, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.
[0032] In addition, in the embodiments of the present application, orientation terms such as "upper", "lower", "left", and "right" are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, which are used for relative description and clarification and may change accordingly with the change of the orientation of the components placed in the accompanying drawings.
[0033] In the embodiments of the present application, unless otherwise clearly defined and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral body; it can be directly connected or indirectly connected through an intermediate medium.
[0034] In the embodiments of the present application, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.
[0035] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.
[0036] Quantum well semiconductor lasers have a wide range of applications in many fields such as optical communication (fiber optic communication for transmitting information), optical storage (such as Blu-ray discs, etc.), and laser processing (such as laser cutting and welding). However, quantum well semiconductor lasers have the problem of a relatively low threshold of catastrophic optical damage (COD), which limits the further development of quantum well semiconductor lasers in high-power application scenarios.
[0037] Currently, the methods for increasing the COD threshold of quantum well semiconductor lasers mainly fall into the following categories: First, reducing the photon density, that is, usually adopting an asymmetric large optical cavity structure, reducing the light absorption in the active region by increasing the waveguide layer thickness, and reducing the optical power density on the cavity surface; Second, reducing the non-radiative recombination rate, and the main methods include: vacuum cleavage technology, surface treatment, deposition of a passivation layer, aluminum-free active region, non-injection of cavity surface current, etc.; Third, reducing the light absorption on the cavity surface, that is, increasing the bandgap width of the material near the cavity surface, and the main methods adopted include using a strained quantum well structure laser or forming a non-absorbing window near the cavity surface of the quantum well semiconductor laser.
[0038] Quantum well intermixing technology is a method for preparing non-absorbing windows and improving the performance of quantum well semiconductor lasers. The quantum well intermixing methods in related technologies mainly include ion implantation, impurity diffusion, etc. However, these methods have problems such as complex processes and difficulty in precisely controlling the impurity diffusion region. For example, ion implantation may damage the lattice structure of semiconductor materials and affect device performance; during the impurity diffusion process, the distribution of impurities is difficult to accurately control, easily resulting in uneven quantum well intermixing. In the field of photon integration technology, the demand for semiconductor lasers that can emit multiple wavelengths simultaneously is also becoming increasingly urgent. Existing technical means still have certain limitations in achieving efficient and precise quantum well intermixing.
[0039] An embodiment of the present application provides a method for manufacturing a semiconductor laser. Referring to Figure 1 , the method for manufacturing the semiconductor laser of the present application includes:
[0040] S100: Prepare a quantum well epitaxial wafer;
[0041] S200: Prepare an inhibition layer in a first region on a preset surface of the quantum well epitaxial wafer, and prepare a dielectric layer in a second region on the preset surface;
[0042] S300: Irradiate the second region with a laser beam. The inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; the dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer.
[0043] In an embodiment of the present application, the preset surface of the quantum well epitaxial wafer refers to the surface that needs to be irradiated with a laser beam during the manufacturing process.
[0044] In an embodiment of the present application, the inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer. When the quantum well epitaxial wafer is irradiated with a laser, the inhibition layer can be used to inhibit the intermixing of quantum wells on the preset surface, that is, the first region is the region on the quantum well epitaxial wafer where quantum well intermixing does not need to occur.
[0045] In an embodiment of the present application, the second region is the region to be prepared. Under the irradiation of the laser beam, it can induce impurity diffusion in the quantum wells in the second region or change the quantum well structure in the second region, thereby realizing local adjustment of the bandgap in the second region and widening the bandgap. The dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer and can promote the intermixing or structural change of the quantum wells in the second region under the irradiation of the laser beam.
[0046] The wider the bandgap of the second region, the more the wavelength in the second region will shift to the blue. The region with a blue-shifted wavelength is insensitive to the light wavelength emitted by the laser. Therefore, after the second region is fabricated, it can be used to make a semiconductor laser. For the semiconductor laser fabricated in this way, due to the broadening of the bandgap of the quantum well material in the second region, the wavelength shifts to the blue, so the absorption of the light wavelength emitted by the laser decreases, the optical power density is reduced, that is, the optical catastrophic damage threshold is increased, thereby reducing the excessive concentration of light energy in this region and reducing the damage of the semiconductor laser.
[0047] In the embodiments of the present application, the second region may include regions such as the active region, the resonant cavity, and the cavity surface of the laser that require an increased COD threshold. By way of example, referring to Figure 2 , Figure 2 shows the hybrid region of the front and rear cavity surfaces 21 of the semiconductor laser 2. The cavity surface 21 region is the two end faces of the semiconductor laser 2, and the laser generated by the semiconductor laser 2 is output from one of the end faces. The middle region is the resonant cavity 22. The optical power density near the cavity surface 21 of the semiconductor laser 2 is usually very high, and light absorption and heat accumulation are likely to occur, resulting in optical catastrophic damage (COD). In order to improve the reliability of the semiconductor laser 2, the structure of the cavity surface 21 region can be subjected to quantum well intermixing, that is, the case where the second region is the cavity surface 21 region. In this way, the optical catastrophic damage (COD) threshold of the cavity surface 21 region can be increased, and the damage of the cavity surface 21 of the semiconductor laser 2 during use can be reduced.
[0048] Furthermore, the cavity surface 21 region is the region where the semiconductor laser 2 emits laser light. On the fabricated laser, the width of each cavity surface 21 region is generally 30 micrometers (μm) to 50 micrometers (μm), and the length is the same as the width of the light-emitting cavity surface 21 region of the semiconductor laser 2.
[0049] In the embodiments of the present application, the laser beam used to irradiate the second region generally uses a highly focused pulsed laser. The highly focused laser beam can concentrate the energy in a very small region (usually on the micrometer or sub-micrometer scale), thereby achieving precise processing of the local region (the second region).
[0050] In the method for preparing a semiconductor laser according to an embodiment of the present application, since a first region and a second region are distinguished on a preset surface of a quantum well epitaxial wafer, a suppression layer capable of suppressing the action of a laser beam on the quantum well epitaxial wafer is prepared in the first region, and a dielectric layer capable of promoting the action of the laser beam on the quantum well epitaxial wafer is prepared in the second region. When the laser beam irradiates the preset surface of the quantum well epitaxial wafer, the quantum well epitaxial wafer in the first region where the suppression layer is prepared will not undergo mixing or structural change, while the quantum well epitaxial wafer in the second region where the dielectric layer is prepared will undergo quantum well mixing or structural change under the promotion of the dielectric layer. Therefore, the method for preparing a semiconductor laser according to an embodiment of the present application can precisely induce quantum well mixing in a specific region (the second region) on the quantum well epitaxial wafer.
[0051] Applying the method for preparing a semiconductor laser according to an embodiment of the present application in a photonic integrated chip can flexibly adjust the performance of a quantum well semiconductor laser according to the requirements of different photonic devices, improve the overall performance and integration degree of the photonic integrated chip, and reduce production costs. For example, in an optical communication chip, the coupling efficiency between the laser and the waveguide can be improved, and the signal transmission loss can be reduced.
[0052] Referring to Figure 3 , in step S200 of preparing a suppression layer in the first region on the preset surface of the quantum well epitaxial wafer and preparing a dielectric layer in the second region on the preset surface, it includes:
[0053] S210: Prepare a prefabricated layer by depositing a first type of material on the preset surface;
[0054] S220: Retain the prefabricated layer in the first region to form a suppression layer; Remove the prefabricated layer in the second region to form a vacant region;
[0055] S230: Prepare a dielectric layer by depositing a second type of material in the vacant region;
[0056] In an embodiment of the present application, the preparation of the prefabricated layer, the suppression layer, and the dielectric layer can all use thin film deposition techniques, such as chemical vapor deposition, physical vapor deposition, or atomic layer deposition, to uniformly deposit the required materials on the preset surface of the quantum well epitaxial wafer.
[0057] In an embodiment of the present application, first, a prefabricated layer is prepared on the preset surface of the quantum well epitaxial wafer, that is, the prefabricated layer completely covers the preset surface, or the prefabricated layer at least covers the first region and the second region on the preset surface. At this time, the surfaces of the first region and the second region both have the prefabricated layer.
[0058] Furthermore, since the first region needs to suppress the irradiation action of the laser beam and the second region needs to promote the irradiation action of the laser beam, the prefabricated layer can be made of the same material as the suppression layer, that is, the first type of material, and the first type of material is used to suppress the action of the laser beam on the quantum well epitaxial wafer.
[0059] In this way, a prefabricated layer is prepared on both the first region and the second region of the preset surface. At this time, if the prefabricated layer in the second region is removed, a vacant region will be formed in the second region, that is, the preset surface of the quantum well epitaxial wafer in the vacant region is exposed. Then, in the vacant region, that is, in the region of the preset surface exposed in the vacant region, a second type of material is prepared to form a dielectric layer.
[0060] The embodiment of the present application provides a method for manufacturing a semiconductor laser. By removing the prefabricated layer in the second region on the prefabricated layer to form a vacant region, the boundary of the suppression layer prepared on the second region and the first region can be precisely controlled, so that the regional distribution of the suppression layer and the dielectric layer prepared in the vacant region is clear, and the manufacturing precision of the semiconductor laser is improved.
[0061] In another embodiment, referring to Figure 4 , the method for manufacturing a semiconductor laser includes:
[0062] S260: Isolate a first region and a second region on the preset surface through an isolation structure;
[0063] S270: Lay a first material in the first region to form a suppression layer, and lay a second material in the second region to form a dielectric layer.
[0064] In the embodiment of the present application, the isolation structure can adopt a physical method or a chemical method. The isolation structure can adopt physical deposition isolation, metal oxide isolation, air gap isolation, etc., and is used to isolate the preset surface of the quantum well epitaxial wafer into a first region and a second region.
[0065] The embodiment of the present application provides a method for manufacturing a semiconductor laser. By directly dividing the first region and the second region through the isolation structure, the step of removing the prefabricated layer in the second region is reduced, the manufacturing process and cost are simplified, and the waste of the first type of material is also reduced.
[0066] Referring to Figure 5 , in the step S220 of forming a suppression layer by retaining the prefabricated layer in the first region and removing the prefabricated layer in the second region to form a vacant region, it includes:
[0067] S221: Based on preset performance parameters, determine the position parameters and size parameters of the second region;
[0068] S222: Based on the position parameters and size parameters, etch the first type of material corresponding to the second region to form a vacant region.
[0069] In the embodiment of the present application, photolithography and etching processes can be adopted. Through photolithography and etching, the shapes and sizes of the suppression layer and the dielectric layer can be precisely controlled.
[0070] In the embodiments of the present application, the preset performance parameters refer to the performance parameters that the semiconductor laser is preset to achieve. Based on these, the size, shape, etc. of the cavity surface region can be determined. According to the size, shape, and other dimensions of the cavity surface region, the position, size, and shape of the second region are determined on the quantum well epitaxial wafer.
[0071] Exemplarily, the width of the light-emitting cavity surface region can be 60 μm to 300 μm, that is, corresponding to the size of the light-emitting cavity surface. The prefabricated layer within the second region with a width of 60 μm to 100 μm is etched off on the preset surface where the prefabricated layer has been prepared. The shape of the light-emitting cavity surface region is rectangular. When fabricating a strip single-tube semiconductor laser, window regions with different widths can be prepared.
[0072] In some possible embodiments of the present application, the first type of material includes SiO2 and TiO2. Referring to Figure 6 and Figure 8 , in step S210 of preparing the first type of material to form a prefabricated layer on the preset surface, it includes:
[0073] S211: Prepare a third SiO2 layer 31 on the preset surface corresponding to the first region;
[0074] S212: Prepare a TiO2 layer 32 on the surface of the third SiO2 layer 31.
[0075] In the embodiments of the present application, the III-V semiconductor laser is a type of laser based on III-V compound semiconductor materials. The III-V compound can be gallium arsenide (GaAs), indium phosphide (InP), gallium nitride (GaN), etc. For the III-V semiconductor laser, the first type of material can be selected as a titanium dioxide (TiO2) layer, Si x N y layer (Si x N y is a general formula representing a certain form of silicon nitride, where x and y are variables representing the number of silicon and nitrogen atoms), or a composite layer of a silicon dioxide layer (SiO2) and other materials to inhibit quantum well intermixing.
[0076] In the embodiments of the present application, the first type of material includes SiO2 (silicon dioxide) and TiO2 (titanium dioxide). Referring to Figure 8 , a third SiO2 layer 31 is prepared in the first region of the preset surface, and a TiO2 layer 32 is prepared on the basis of the third SiO2 layer 31. The thicknesses of the third SiO2 layer 31 and the TiO2 layer 32 can be adjusted according to requirements. Exemplarily, in the embodiments of the present application, a 100-nanometer (nm) SiO2 layer and a 100-nanometer (nm) TiO2 layer 32 are deposited on the preset surface. Thus, the third SiO2 layer 31 and the TiO2 layer 32 formed on the preset surface are the inhibition layer 3.
[0077] In some possible embodiments of the present application, the second type of material includes Si and SiO2. Referring to Figure 7 and Figure 8 , in step S230 of preparing the second type of material in the vacant area to form the dielectric layer 4, it includes:
[0078] S231: Prepare a first SiO2 layer 41 on the preset surface corresponding to the second region;
[0079] S232: Prepare a Si layer 42 on the surface of the first SiO2 layer 41;
[0080] S233: Prepare a second SiO2 layer 43 on the surface of the Si layer 42.
[0081] In the embodiments of the present application, the second type of material used to promote the action of the laser beam on the quantum well epitaxial wafer 1 can be an SiO2 layer, Si x N y layer, SiO2-Si (silicon) composite layer, SiO2-Zn (zinc) composite layer (composite or doped material), SiO2-Cu (copper) composite layer, etc., to promote quantum well intermixing, which needs to be matched according to the material system.
[0082] In the embodiments of the present application, after the third SiO2 layer 31 and the TiO2 layer 32 have been prepared on the preset surface, it is necessary to etch away the third SiO2 layer 31 and the TiO2 layer 32 in the second region to expose the preset surface in the second region. Then, prepare the first SiO2 layer 41 on the preset surface in the second region, prepare the Si layer 42 on the surface of the first SiO2 layer 41, and prepare the second SiO2 layer 43 on the surface of the Si layer 42. In this way, a three-layer composite of the first SiO2 layer 41, the Si layer 42, and the second SiO2 layer 43 will be formed on the preset surface in the second region, and this three-layer composite is the dielectric layer 4.
[0083] In the embodiments of the present application, referring to Figure 8 , Figure 8 shows a cross-sectional view of the suppression layer 3 and the dielectric layer 4 prepared on the quantum well semiconductor. Figure 8 The region in the middle part in Figure 8 is the non-front and rear cavity surface region of the resonant cavity, and the suppression layer 3 formed by the third SiO2 layer 31 and the TiO2 layer 32 is prepared in this region.
[0084] In the embodiments of the present application, the thicknesses of the first SiO2 layer 41, the Si layer 42, and the second SiO2 layer 43 can be adjusted according to requirements. For example, in the embodiments of the present application, a 100-nm SiO2 layer, a 20-nm Si layer 42, and a 400-nm SiO2 layer are prepared on a preset surface.
[0085] Referring to Figure 9 , before the step S220 of forming an inhibition layer by retaining the prefabricated layer in the first region and removing the prefabricated layer in the second region to form a vacant region, the method for manufacturing a semiconductor laser further includes:
[0086] S240: Lay a protective layer on the surface of the prefabricated layer, and the protective layer covers at least the first region.
[0087] In the embodiments of the present application, after etching the prefabricated layer in the second region, when preparing a dielectric layer in the second region, at the connection between the second region and the first region, the dielectric layer may be exposed and cover the prefabricated layer in the first region at the connection. Therefore, a protective layer can be laid on the surface of the prefabricated layer in the first region.
[0088] In the embodiments of the present application, the second material type can adhere to the protective layer, and the protective layer is used to isolate the prefabricated layer on the first region and the second type of material. The protective layer can be a photoresist, an organic polymer, etc. The photoresist can be removed using a photoresist stripper, and the organic polymer can be removed by a solvent or plasma.
[0089] Referring to Figure 9 , after the step S230 of preparing a second type of material in the vacant region to form a dielectric layer, the method for manufacturing a semiconductor laser further includes:
[0090] S250: Remove the protective layer and the second type of material attached thereto.
[0091] Referring to Figure 10 and Figure 11 , in the step S300 of irradiating the second region 12 with a laser beam 51, where the inhibition layer is configured to limit the action of the laser beam 51 on the quantum well epitaxial wafer 1; the dielectric layer is configured to promote the action of the laser beam 51 on the quantum well epitaxial wafer 1, includes:
[0092] S310: Adjust the parameters of the laser beam 51 based on preset parameters and characteristic parameters of the second region 12;
[0093] S320: Use the adjusted laser beam 51 to irradiate the second region 12.
[0094] Among them, the preset parameters include at least the depth and range of quantum well diffusion; the characteristic parameters include at least the shape parameters of the second region 12; the parameters of the laser beam 51 include at least: the shape parameters, size parameters, power parameters, and wavelength parameters of the laser beam 51.
[0095] In the embodiments of the present application, the parameters of the laser beam 51 of the high-power pulsed laser 5 can be adjusted by preset parameters and the characteristic parameters of the second region 12. For example, through a high-precision optical focusing system, the laser beam 51 is focused on the second region 12. The length of the beam spot of the laser beam 51 on the surface of the second region can be 60 μm to 100 μm, the wavelength of the laser beam 51 can be 780 nm to 1064 nm, the shape and size of the laser beam 51 match the shape and size of the second region 12, and the energy density at the focus of the laser beam 51 after focusing is generally not less than 1 J / cm 2 (Joule per square centimeter).
[0096] Referring to Figure 11 , in the embodiments of the present application, the laser gradually irradiates the second region 12 in a scanning manner from one side to the other side of the quantum well epitaxial wafer 1, and the power and spot position of the laser beam 51 are kept stable during the irradiation process. Since the inhibition layer is prepared in the first region 11, the first region 11 will not be contaminated due to the irradiation of the laser beam 51, and by adjusting the parameters of the laser beam 51, the possibility of the laser beam 51 irradiating the first region 11 can be reduced.
[0097] Referring to Figure 11 , in the embodiments of the present application, there are multiple second regions 12, and the edges of the multiple second regions 12 are in a connected state. The irradiation time of the laser beam 51 on one second region 12 can be set. After the irradiation time ends, the laser beam 51 is moved to the next unirradiated second region 12.
[0098] In the embodiments of the present application, there is an angle between the preset surface and the laser beam 51, and the angle can be adjusted according to the preparation requirements. For example, the laser beam 51 can irradiate the second region 12 at an angle perpendicular to the preset surface.
[0099] In the embodiments of the present application, the irradiation time of the laser beam 51 on one second region 12 is determined, and this time can be adjusted according to the preparation requirements. For example, the irradiation time of the laser beam 51 on one second region 12 is 1 s (second).
[0100] Referring to Figure 10 , in step S300 where the inhibition layer is configured to limit the action of the laser beam on the quantum well epitaxial wafer and the dielectric layer is configured to promote the action of the laser beam on the quantum well epitaxial wafer by irradiating the second region with the laser beam, it further includes:
[0101] S330: Monitoring the temperature and optical characteristics of the second region irradiated by the laser beam;
[0102] S340: Adjusting the parameters of the laser beam based on the monitoring results.
[0103] In the embodiments of the present application, a monitoring system, such as a combination of an optical microscope and a power monitor, can be used to monitor the temperature and optical properties of the second region irradiated by the laser beam, thereby improving the control of the quantum well impurity diffusion process.
[0104] In the embodiments of the present application, under the irradiation of the laser beam, by controlling the laser parameters (power, wavelength, irradiation time, etc.), the diffusion depth and range of impurities and defects can be controlled, thereby realizing quantum well intermixing in the second region.
[0105] In the embodiments of the present application, quantum well intermixing is achieved through a certain technology to accelerate the diffusion of doped atoms, vacancies, etc., so that the material composition at the quantum well boundary changes, thereby increasing the bandgap width of the material in this region. According to the relationship equation E = hv between the bandgap width of the semiconductor material and the emission wavelength, where E represents the photon energy, h is Planck's constant, and v is the frequency of light. Since the frequency of light v = c / λ, therefore, through conversion, it can be obtained that E = hc / λ, where λ is the wavelength of light and c is the speed of light. Therefore, when the bandgap width increases, the emission wavelength will decrease, that is, blue shift.
[0106] Referring to Figure 12 , Figure 12 shows a quantum well structure formed by two materials, gallium arsenide (GaAs) and indium gallium arsenide (InGaAs). Figure 12 The structure on the left in Figure 12 is the structure where the quantum well has not undergone intermixing. Under the irradiation of the laser beam and the promotion of the dielectric layer, the substances between the quantum wells will undergo intermixing. As Figure 12 shown in the structure on the right in Figure 12 , the In (indium) element in InGaAs has been intermixed into the GaAs on both sides.
[0107] Referring to Figure 10 , in step S300 where the suppression layer is configured to limit the action of the laser beam on the quantum well epitaxial wafer and the dielectric layer is configured to promote the action of the laser beam on the quantum well epitaxial wafer by irradiating the second region with the laser beam, it further includes:
[0108] S350: Anneal the second region after the laser beam irradiation;
[0109] S360: Remove the suppression layer in the first region and remove the dielectric layer in the second region.
[0110] In the embodiments of the present application, after the laser beam irradiation is completed and the second region is annealed, methods such as chemical solution or reactive ion etching can be used to remove substances such as TiO2, SiO2, Si, etc. on the preset surface, so as to facilitate the subsequent process.
[0111] In the embodiments of the present application, during the preparation process of the photonic integrated chip, the quantum well structure of the semiconductor laser is integrated with other photonic devices (such as waveguides, modulators, etc.) on the same substrate. In the area where quantum well intermixing is required to optimize the performance of the laser, the above-mentioned method of laser beam-induced quantum well intermixing is used for treatment, which can improve the optical coupling efficiency and overall performance between the laser and other photonic devices.
[0112] The embodiments of the present application provide a method for preparing a semiconductor laser, and the steps are as follows:
[0113] S100: Prepare a quantum well epitaxial wafer;
[0114] S211: Prepare a third SiO2 layer on the preset surface corresponding to the first region;
[0115] S212: Prepare a TiO2 layer on the surface of the third SiO2 layer;
[0116] S240: Lay a protective layer on the surface of the prefabricated layer, and the protective layer covers at least the first region;
[0117] S221: Determine the position parameters and size parameters of the second region based on the preset performance parameters;
[0118] S222: Etch the first type of material corresponding to the second region based on the position parameters and size parameters to form a vacant region;
[0119] S231: Prepare a first SiO2 layer on the preset surface corresponding to the second region;
[0120] S232: Prepare a Si layer on the surface of the first SiO2 layer;
[0121] S233: Prepare a second SiO2 layer on the surface of the Si layer;
[0122] S250: Remove the protective layer and the second type of material attached thereto;
[0123] S310: Adjust the parameters of the laser beam based on the preset parameters and the characteristic parameters of the second region;
[0124] S320: Use the adjusted laser beam to irradiate the second region;
[0125] S330: Monitor the temperature and optical properties of the second region irradiated by the laser beam;
[0126] S340: Adjust the parameters of the laser beam based on the monitoring results;
[0127] S350: Anneal the second region irradiated by the laser beam;
[0128] S360: Remove the inhibition layer of the first region and remove the dielectric layer of the second region.
[0129] The serial numbers of the embodiments of the present application above are only for description and do not represent the superiority or inferiority of the embodiments. The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, shall be equally included in the patent protection scope of the present application.
Claims
1. A method for preparing a semiconductor laser, characterized in that: include: Preparation of quantum well epitaxial wafers; Preparing an inhibition layer in a first region of a predetermined surface of the quantum well epitaxial wafer, and preparing a dielectric layer in a second region of the predetermined surface; The second region is irradiated with a laser beam, and the suppression layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; and the dielectric layer is configured to promote the effect of the laser beam on the quantum well epitaxial wafer.
2. The method for preparing a semiconductor laser according to claim 1, in the steps of preparing an inhibition layer in a first region of a predetermined surface of the quantum well epitaxial wafer and preparing a dielectric layer in a second region of the predetermined surface, the method comprising: Prepare a first type of material on the preset surface to form a prefabricated layer; Retaining the prefabricated layer in the first region forms the inhibition layer; removing the prefabricated layer in the second area to form a vacant area; A second type of material is prepared in the vacant area to form the dielectric layer.
3. The method for preparing a semiconductor laser according to claim 2, wherein the inhibition layer is formed on the prefabricated layer retaining the first region; In the step of removing the prefabricated layer in the second area to form a vacant area, the method comprises: Based on the preset performance parameters, determining the position parameters and size parameters of the second area; Based on the position parameter and the size parameter, the first type of material corresponding to the second region is etched to form the vacant region.
4. The method for preparing a semiconductor laser according to claim 2, wherein the inhibition layer is formed on the prefabricated layer retaining the first region; Before the step of removing the prefabricated layer in the second area to form a vacant area, the method further comprises: Laying a protective layer on the surface of the prefabricated layer, wherein the protective layer at least covers the first area; After the step of preparing the second type of material in the vacant area to form the dielectric layer, the method further comprises: The protective layer and the second type of material attached thereto are removed.
5. The method for preparing a semiconductor laser according to claim 2, wherein the second type of material comprises Si and SiO2, and in the step of preparing the second type of material in the vacant area to form the dielectric layer, the method comprises: Prepare a first SiO2 layer on a predetermined surface corresponding to the second region; Preparing a Si layer on the surface of the first SiO2 layer; A second SiO2 layer is prepared on the surface of the Si layer.
6. The method for preparing a semiconductor laser according to claim 2, wherein the first type of material comprises SiO2 and TiO2, and in the step of preparing the first type of material on the preset surface to form a prefabricated layer, the method comprises: Prepare a third SiO2 layer on the preset surface corresponding to the first area; A TiO2 layer is prepared on the surface of the third SiO2 layer.
7. The method for preparing a semiconductor laser according to claim 1, comprising: Isolating the first area and the second area on the preset surface by an isolation structure; The first material is laid in the first area to form the inhibition layer, and the second material is laid in the second area to form the dielectric layer.
8. The method for preparing a semiconductor laser according to claim 1, wherein when the second region is irradiated with a laser beam, the inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; In the step where the dielectric layer is configured to facilitate the effect of the laser beam on the quantum well epitaxial wafer, the method comprises: Adjusting the parameters of the laser beam based on preset parameters and characteristic parameters of the second area; irradiating the second area with the adjusted laser beam; Among them, the preset parameters include at least the depth and range of quantum well diffusion; the characteristic parameters include at least the shape parameters of the second region; the laser beam parameters include at least: shape parameters, size parameters, power parameters, and wavelength parameters of the laser beam.
9. The method for preparing a semiconductor laser according to claim 8, wherein when the second region is irradiated with a laser beam, the inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; In the step where the dielectric layer is configured to facilitate the effect of the laser beam on the quantum well epitaxial wafer, the method further comprises: monitoring a temperature and an optical property of the second area irradiated by the laser beam; Parameters of the laser beam are adjusted based on the monitoring results.
10. The method for preparing a semiconductor laser according to claim 1, wherein when the second region is irradiated with a laser beam, the inhibition layer is configured to limit the effect of the laser beam on the quantum well epitaxial wafer; In the step where the dielectric layer is configured to facilitate the effect of the laser beam on the quantum well epitaxial wafer, the method further comprises: annealing the second region after being irradiated with the laser beam; The inhibition layer in the first region is removed, and the dielectric layer in the second region is removed.