Semiconductor laser and method for manufacturing the same

Abstract

The application relates to the technical field of lasers, in particular to a semiconductor laser and a preparation method thereof. The semiconductor laser comprises a stacked structure, the stacked structure comprises a ridge waveguide, the stacked structure is divided into a laser oscillation area and a beam angle regulation area arranged in a first direction, a part of the ridge waveguide, which is in contact with a light-emitting cavity surface, has a plurality of grooves arranged at intervals along a second direction, and the ridge waveguide between two adjacent grooves serves as a regulation waveguide; a P-type main electrode is located on the top surface of the ridge waveguide of the laser oscillation area; a distributed electrode comprises a plurality of regulation electrodes, and the regulation electrodes are located on the top surfaces of the corresponding regulation waveguides; wherein each regulation electrode is loaded with a corresponding regulation current to regulate the beam angle of initial laser in the beam angle regulation area, and then target laser is output from the light-emitting cavity surface. The application realizes free regulation of the beam angle of laser emission without setting an additional beam shaping system, which is beneficial to simplifying the system structure and reducing the cost.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lasers, and particularly relates to a semiconductor laser and a preparation method thereof. BACKGROUND

[0002] Semiconductor lasers have the advantages of small volume, high efficiency and low power consumption, and have important applications in laser communication, laser pumping, laser sensing and many other fields. For a traditional edge-emitting laser, laser oscillates between the front and rear cavity surfaces, and is emitted from one cavity surface. According to a special structural design, different functions can be achieved, for example: single transverse mode emission can be achieved by narrowing the waveguide width of the laser to 3-5 microns; narrow-linewidth laser can be achieved by using a grating structure; and the polarization state of the laser can be selected by using a compressively strained quantum well. However, the laser emission angle of the edge-emitting semiconductor laser is generally determined by the waveguide thickness, waveguide width and material refractive index. When the device structure is fixed, the beam divergence angle is fixed and cannot be adjusted, and only optical lenses can be added externally to shape the beam to achieve beam focusing, divergence or angle deflection. However, in many applications, there is a need to shape the light emitted by the semiconductor laser, and therefore multiple optical lenses are required, resulting in an increase in system size and high labor cost for debugging.

[0003] In addition, due to the special waveguide structure of the active region of the traditional semiconductor laser, the output beam has inherent and serious asymmetry: the divergence angle in the "slow axis" direction parallel to the active layer is small, usually 10-30°, while the divergence angle in the "fast axis" direction perpendicular to the active layer is extremely large, usually 25-60°, resulting in an uncontrollable elliptical shape of the exit spot. The biggest problem is that the refractive index of the ridge waveguide region in the lateral direction is fixed at the light-emitting cavity surface position of the traditional edge-emitting semiconductor laser, resulting in a fixed emission angle of the beam. This inherent beam quality problem seriously restricts its direct application in scenarios that require high-quality and flexible controllable beams. If a complex external optical system such as a fast-axis collimating cylindrical lens, a slow-axis collimating cylindrical lens and a subsequent beam shaper is used to correct and shape the beam, the divergence angle can be compressed to a certain extent, but this will not only increase the system size, cost and assembly and adjustment difficulty, but more importantly, it cannot be dynamically adjusted once it is fixed. This means that the beam shape of the traditional semiconductor laser, such as spot shape, divergence angle and even energy distribution, is fixed after it leaves the factory, lacking flexibility, programmability and dynamic control capability. Therefore, developing a new type of semiconductor laser structure and control method that can overcome this defect from the source has become a key technical problem to be solved in the field. SUMMARY

[0004] Therefore, the application aims to provide a semiconductor laser and a preparation method thereof, which can realize free regulation of laser emission beam angle without setting an additional beam shaping system, and are beneficial to simplify system structure and reduce cost.

[0005] To achieve the above-mentioned purposes, the technical scheme of the application is as follows:

[0006] The application provides a semiconductor laser, which comprises a stacked structure, the stacked structure comprising a ridge waveguide and an N-type electrode layer, a substrate layer, an N-type cladding layer, an N-type waveguide layer, an active layer and a first P-type waveguide layer stacked in sequence, the ridge waveguide extending along a first direction on a part of the top surface of the first P-type waveguide layer, the stacked structure being divided into a laser oscillation area arranged in the first direction and a beam angle regulation area, an end surface of the beam angle regulation area away from the laser oscillation area being an output cavity surface, a part of the ridge waveguide adjacent to the output cavity surface having a plurality of grooves arranged at intervals along a second direction, and the ridge waveguide between two adjacent grooves serving as a regulation waveguide; a P-type main electrode, which is located on the top surface of the ridge waveguide in the laser oscillation area; and a distributed electrode, which comprises a plurality of regulation electrodes arranged at intervals along the second direction, the regulation electrodes corresponding to the regulation waveguides one by one and being located on the top surfaces of the corresponding regulation waveguides; wherein the P-type main electrode is loaded with a corresponding current to realize output of initial laser from the laser oscillation area to the beam angle regulation area, and each regulation electrode is loaded with a corresponding regulation current to realize regulation of the beam angle of the initial laser by the beam angle regulation area, so that target laser is output from the output cavity surface.

[0007] Further, each regulation electrode is loaded with a corresponding regulation current to adjust the refractive index of each regulation waveguide, and the greater the regulation current loaded by the regulation electrode, the higher the refractive index of the corresponding regulation waveguide.

[0008] Further, an end surface of the laser oscillation area away from the beam angle regulation area is a rear cavity surface; a part of the ridge waveguide adjacent to the beam angle regulation area and located in the laser oscillation area has lateral gratings on both sides in the second direction, the P-type main electrode is located on the top surface of the remaining ridge waveguide in the laser oscillation area except the lateral gratings, and when the P-type main electrode is loaded with a corresponding current, the rear cavity surface and the lateral gratings form a resonant cavity to output the initial laser.

[0009] Further, the ridge waveguide comprises a second P-type waveguide layer and a P-type cover layer, the second P-type waveguide layer being located on a part of the top surface of the first P-type waveguide layer, and the P-type cover layer being located on the top surface of the second P-type waveguide layer away from the first P-type waveguide layer.

[0010] Further, the semiconductor laser further comprises an insulating layer, which is located on the top surface of the stacked structure except the P-type main electrode and the regulation electrodes.

[0011] Further, the distributed electrode includes N regulating electrodes, N being an integer greater than 1; the distributed electrode further includes N lead wires on the insulating layer, the lead wires corresponding to the regulating electrodes one by one, and one end of the lead wire being connected to the corresponding regulating electrode; the stack structure has a first side and a second side arranged in the second direction, the lead wires corresponding to the regulating electrodes adjacent to the first side extending from the corresponding regulating electrodes to the first side, and the lead wires corresponding to the regulating electrodes adjacent to the second side extending from the corresponding regulating electrodes to the second side.

[0012] Further, the current loaded by the N regulating electrodes arranged at intervals in the second direction gradually decreases from the middle to both sides, and the beam angle regulation region performs beam focusing on the initial laser to output the target laser.

[0013] Further, the current loaded by the N regulating electrodes arranged at intervals in the second direction gradually decreases from both sides to the middle, and the beam angle regulation region performs beam divergence on the initial laser to output the target laser.

[0014] Further, the current loaded by the N regulating electrodes arranged at intervals in the second direction gradually increases from one side to the other side, and the beam angle regulation region performs beam deflection on the initial laser to output the target laser.

[0015] The application further provides a preparation method of a semiconductor laser, for preparing the semiconductor laser, the preparation method of the semiconductor laser comprising: forming a stack structure, the stack structure including a ridge waveguide and an N-type electrode layer, a substrate layer, an N-type cladding layer, an N-type waveguide layer, an active layer and a first P-type waveguide layer stacked in sequence, the ridge waveguide extending along a first direction on part of the top surface of the first P-type waveguide layer, the stack structure being divided into a laser oscillation region arranged in the first direction and a beam angle regulation region, an end surface of the beam angle regulation region away from the laser oscillation region being an out-coupling cavity surface, part of the ridge waveguide adjacent to the out-coupling cavity surface having a plurality of grooves arranged at intervals in a second direction, and the ridge waveguide between two adjacent grooves serving as a regulation waveguide; forming a P-type main electrode, the P-type main electrode being located on the top surface of the ridge waveguide in the laser oscillation region; and forming a distributed electrode, the distributed electrode including a plurality of regulating electrodes arranged at intervals in the second direction, the regulating electrodes corresponding to the regulation waveguides one by one, and the regulating electrodes being located on the top surfaces of the corresponding regulation waveguides.

[0016] Compared with the prior art, the present invention can achieve the following beneficial effects: The semiconductor laser provided by the present invention has the function of beam divergence angle control, which helps to simplify the complexity of subsequent beam shaping and reduce costs. Specifically, the present invention introduces a periodic structure at the output cavity surface to realize a periodic refractive index distribution in the lateral direction of the laser at the output cavity surface, and designs a controllable electrode in this region. Applying current to the controllable electrode forms a controllable carrier distribution. Since the refractive index of the semiconductor material is related to the carrier distribution, the setting of the controllable electrode makes the refractive index in this region controllable, thereby causing the laser passing through the output cavity surface to be affected by the refractive index change, and the beam shape changes. By applying a designed current to each controllable electrode in the distributed electrode, the lateral refractive index at the output cavity surface can have multiple distribution forms, thereby realizing the functions of beam focusing, divergence or deflection.

[0017] Compared to using external optical lenses to control the laser beam, such as focusing lenses, beam expanders, and reflecting mirrors to shape the laser beam, this invention controls the lateral refractive index distribution in the laser emission cavity area through distributed electrodes. By modulating the refractive index distribution, the beam angle control function on the laser chip can be realized. Only one chip is needed to achieve free control of the laser emission beam angle, without the need for additional optical paths and beam shaping systems. This simplifies the system structure and size, and reduces manual debugging costs and component setup costs. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 A schematic diagram of the structure of the semiconductor laser described in the embodiments of the present invention;

[0020] Figure 2 A top view of the semiconductor laser described in the embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the light-emitting cavity surface of the semiconductor laser described in the embodiments of the present invention;

[0022] Figure 4 This is a schematic diagram illustrating the light output of the semiconductor laser under three different refractive index distributions as described in the embodiments of the present invention. Figure 4 (a) shows the refractive index distribution when the beam is focused. Figure 4 (b) shows the refractive index distribution when beam divergence is achieved. Figure 4 (c) shows the refractive index distribution when beam deflection is achieved. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0025] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, 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 on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] refer to Figures 1 to 3This invention provides a semiconductor laser, comprising: a stacked structure, the stacked structure including a ridge waveguide and sequentially stacked N-type electrode layer 101, substrate layer 102, N-type cladding layer 103, N-type waveguide layer 104, active layer 105, and a first P-type waveguide layer 1061. The ridge waveguide extends along a first direction X on a portion of the top surface of the first P-type waveguide layer 1061. The stacked structure is divided into a laser oscillation region 201 and a beam angle control region 202 arranged along the first direction X. The end face of the beam angle control region 202 away from the laser oscillation region 201 is a light-emitting cavity surface 208. The portion of the ridge waveguide connected to the light-emitting cavity surface 208 has a plurality of grooves 112 spaced along a second direction Y. The ridge between two adjacent grooves 112 forms a ridge. The waveguide serves as the control waveguide 207; the P-type main electrode 111 is located on the top surface of the ridge waveguide in the laser oscillation region 201; the distributed electrode 109 includes multiple control electrodes 1091 arranged at intervals along the second direction Y, each control electrode 1091 corresponding to a control waveguide 207, and the control electrode 1091 is located on the top surface of the corresponding control waveguide 207; wherein, the P-type main electrode 111 is loaded with a corresponding current to realize the output of the initial laser from the laser oscillation region 201 to the beam angle control region 202, and each control electrode 1091 is loaded with a corresponding control current to realize the beam angle control region 202 to control the beam angle of the initial laser, and then output the target laser from the output cavity surface 208. Figure 2 In the laser oscillation zone 201, the ring-shaped black dashed arrow indicates laser oscillation, and the red arrow pointing from the laser oscillation zone 201 to the beam angle control zone 202 indicates the direction of light output.

[0029] In some embodiments, each control electrode 1091 is loaded with a corresponding control current to adjust the refractive index of each control waveguide 207. The larger the control current loaded on the control electrode 1091, the higher the refractive index of the corresponding control waveguide 207. Specifically, after the P-type main electrode 111 is energized, laser oscillation is generated in the laser oscillation region 201 until the initial laser is output. The initial laser is transmitted to the output cavity surface 208 through the beam angle control region 202. A specific current is applied to each independent control electrode 1091, so that the initial laser transmitted to the beam angle control region 202 is modulated by a specific refractive index, the beam angle changes, and then the target laser is output from the output cavity surface 208.

[0030] In some embodiments, the end face of the laser oscillation region 201 away from the beam angle control region 202 is the rear cavity surface 206; the portion of the ridge waveguide adjacent to the beam angle control region 202 and located in the laser oscillation region 201 has lateral gratings 110 on both sides in the second direction Y; the P-type main electrode 111 is located on the top surface of the remaining ridge waveguide in the laser oscillation region 201 excluding the lateral gratings 110; when the P-type main electrode 111 is loaded with a corresponding current, the rear cavity surface 206 and the lateral gratings 110 form a resonant cavity to output the initial laser. The lateral gratings 110 are formed by etching channels spaced apart on both sides of the ridge waveguide in the second direction Y; when the P-type main electrode 111 is loaded with a corresponding current, the laser is oscillated and amplified in the resonant cavity until the lasing threshold is reached, after which the initial laser is output.

[0031] In some embodiments, the ridge waveguide includes a second P-type waveguide layer 1062 and a P-type capping layer 107. The second P-type waveguide layer 1062 is located on a portion of the top surface of the first P-type waveguide layer 1061, and the P-type capping layer 107 is located on the top surface of the second P-type waveguide layer 1062 away from the first P-type waveguide layer 1061. The second P-type waveguide layer 1062 and the first P-type waveguide layer 1061 are integral films made of the same material and formed in the same step.

[0032] In some embodiments, the semiconductor laser further includes an insulating layer 108 located on the top surface of the stacked structure outside the P-type main electrode 111 and the control electrode 1091.

[0033] In some embodiments, the distributed electrode 109 includes N control electrodes 1091, where N is an integer greater than 1, for example, N is 8 or 9. The distributed electrode 109 also includes N leads 1092 located on the insulating layer 108, each lead 1092 corresponding to a control electrode 1091, and one end of each lead 1092 is connected to the corresponding control electrode 1091. The stacked structure has a first side and a second side arranged in a second direction Y. The leads 1092 corresponding to a portion of the control electrodes 1091 adjacent to the first side extend from the corresponding control electrode 1091 toward the first side, and the leads 1092 corresponding to the remaining control electrodes 1091 adjacent to the second side extend from the corresponding control electrode 1091 toward the second side. This facilitates the rational arrangement of the leads 1092 and avoids increasing the size of the semiconductor laser.

[0034] In some examples, N is an even number greater than 1. The leads 1092 corresponding to the N / 2 control electrodes 1091 adjacent to the first side extend from the corresponding control electrodes 1091 toward the first side, and the leads 1092 corresponding to the remaining N / 2 control electrodes 1091 adjacent to the second side extend from the corresponding control electrodes 1091 toward the second side.

[0035] In some embodiments, reference Figure 4In (a), the current applied to the N control electrodes 1091 arranged at intervals along the second direction Y gradually decreases from the center to both sides. The refractive index of the N control waveguides 207 arranged at intervals along the second direction Y also gradually decreases from the center to both sides. The beam angle control region 202 focuses the initial laser beam to output the target laser. That is, a high current is applied to one or two control electrodes 1091 located at the center, and the current applied to the control electrodes 1091 distributed on both sides gradually decreases. This creates a laterally distributed refractive index distribution in the waveguide layer of the device's output cavity surface 208, with a high refractive index at the center and gradually decreasing refractive index on both sides, similar to the refractive index distribution of a convex lens. This refractive index distribution affects the light field transmitted to this location, thereby focusing the beam. Figure 4 The red dashed arrow in (a) indicates that the beam has been focused.

[0036] In some embodiments, reference Figure 4 In (b), the current loaded on the N control electrodes 1091 arranged at intervals along the second direction Y gradually decreases from both sides to the middle, and the refractive index of the N control waveguides 207 arranged at intervals along the second direction Y gradually decreases from both sides to the middle. The beam angle control region 202 diverges the initial laser beam to output the target laser. Figure 4 The red dashed arrow in (b) indicates that the beam has a diverging effect.

[0037] In some embodiments, reference Figure 4 In (c), the current loaded on the N control electrodes 1091 arranged at intervals along the second direction Y gradually increases from one side to the other, the refractive index of the N control waveguides 207 arranged at intervals along the second direction Y gradually increases from one side to the other, and the beam angle control region 202 deflects the initial laser beam to output the target laser. Figure 4 The red dashed arrow in (c) indicates that the beam was deflected.

[0038] In some embodiments, the substrate is an N-type GaAs material; the N-type cladding 103 is an AlGaAs material, wherein the Al composition is in the range of 0.1 to 0.6, the thickness of the N-type cladding 103 can be in the range of 0.5 micrometers to 3 micrometers, and the dopant of the N-type cladding 103 is Si, with a Si doping concentration of 1E18 / cm³. 3 ~8E18 / cm 3 Within the specified range; the N-type waveguide layer 104 is made of AlGaAs material, wherein the Al content is in the range of 0.05~0.7, the thickness of the N-type waveguide layer 104 is in the range of 0.1 μm~10 μm, and the dopant is Si, with a Si doping concentration of 1E16 / cm. 3 ~8E18 / cm 3Within the specified range; the active layer 105 is non-actively doped, and has a barrier layer / quantum well layer / barrier layer structure. The barrier layer is made of AlGaAsP, and the quantum well layer is made of InAlGaAs. The In content in the quantum well layer can be in the range of 0~0.5%, the Al content in the quantum well layer or barrier layer can be in the range of 0~0.5%, the P content in the barrier layer can be in the range of 0~0.2%, the thickness of the barrier layer can be in the range of 1 nm~200 nm, and the thickness of the quantum well layer can be in the range of 1 nm~20 nm. The emission wavelength of the active layer 105 is 700 nm~1200 nm. The P-type waveguide layer can be made of AlGaAs material, where the Al content can be in the range of 0.05~0.7%. The thickness of the P-type waveguide layer can be in the range of 0.1 μm~10 μm. The dopant is C, and the C doping concentration can be 1E16 / cm. 3 ~8E18 / cm 3 Within the specified range; the P-type capping layer 107 is made of GaAs material, with a thickness ranging from 0.1 μm to 3 μm, and the dopant is C, with a C doping concentration of 1E18 / cm². 3 ~1E20 / cm 3 Within the range.

[0039] It should be noted that the semiconductor lasers provided in the above embodiments correspond to a wavelength range of 700nm~1200nm and a material system of GaAs. In some other embodiments, an InP system can also be used to realize semiconductor lasers with a wavelength range of 1200nm~1600nm.

[0040] In some embodiments, the cavity length of the semiconductor laser is in the range of 1 mm to 5 mm.

[0041] In some embodiments, the thickness of the P-type main electrode 111, the control electrode 1091, or the N-type electrode layer 101 is in the range of 200 nanometers to 500 nanometers, and the P-type main electrode 111, the control electrode 1091, or the N-type electrode layer 101 can be an alloy material formed of metals such as titanium, platinum, gold, nickel, and germanium.

[0042] In some embodiments, the insulating layer 108 is made of SiO2 or Si3N4, and the thickness of the insulating layer 108 can be in the range of 50 nanometers to 1000 nanometers.

[0043] In some embodiments, the grating period of the lateral grating 110 is in the range of 100 nanometers to 10 micrometers, the grating duty cycle is between 0.1 and 0.9, the etching depth of the trench forming the lateral light is in the range of 0.1 micrometers to 10 micrometers, and the number of corresponding grating pairs on both sides is in the range of 2 to 50.

[0044] In some embodiments, the width of the groove 112 forming the control waveguide 207 is in the range of 100 nanometers to 10 micrometers, the width of the control waveguide 207 between adjacent grooves 112 is in the range of 100 nanometers to 10 micrometers, the etching depth of the groove 112 is in the range of 0.1 micrometers to 10 micrometers, and the number of grooves 112 is in the range of 3 to 50.

[0045] In some embodiments, the length of the laser oscillation region 201 in the first direction X is in the range of 0.8 mm to 4 mm, the length of the beam angle adjustment region 202 in the first direction X is in the range of 0.2 mm to 1 mm, and the length of the groove 112 in the first direction X is in the range of 0.1 mm to 0.5 mm.

[0046] In some embodiments, the shape of the control electrode 1091 includes, but is not limited to, square, circular, elliptical, rhomboid, etc., and the area of ​​the control electrode 1091 is in the range of 1 square micrometer to 50 square micrometers.

[0047] Another aspect of this invention provides a method for fabricating a semiconductor laser, which includes: forming a stacked structure comprising a ridge waveguide and sequentially stacked N-type electrode layer 101, substrate layer 102, N-type cladding layer 103, N-type waveguide layer 104, active layer 105, and a first P-type waveguide layer 1061. The ridge waveguide extends along a first direction X on a portion of the top surface of the first P-type waveguide layer 1061. The stacked structure is divided into a laser oscillation region 201 and a beam angle control region 202 arranged in the first direction X. The beam angle control region 202 is located away from the laser oscillation region. The end face of the optical oscillation region 201 is the light-emitting cavity surface 208. The portion of the ridge waveguide connected to the light-emitting cavity surface 208 has multiple grooves 112 arranged at intervals along the second direction Y. The ridge waveguide between two adjacent grooves 112 serves as a control waveguide 207. A P-type main electrode 111 is formed, which is located on the top surface of the ridge waveguide of the laser oscillation region 201. A distributed electrode 109 is formed, which includes multiple control electrodes 1091 arranged at intervals along the second direction Y. The control electrodes 1091 correspond one-to-one with the control waveguides 207, and the control electrodes 1091 are located on the top surface of the corresponding control waveguides 207.

[0048] Specifically, in some implementations, forming a stacked structure includes: taking a substrate and sequentially preparing an N-type cladding layer 103, an N-type waveguide layer 104, an active layer 105, a P-type waveguide layer, and a P-type capping layer on the substrate through epitaxial growth to obtain a substrate containing an epitaxial structure; preparing a ridge waveguide on the surface of the substrate containing the epitaxial structure through photolithography and dry etching processes to obtain a wafer containing a ridge waveguide; then preparing a lateral grating 110 and a groove 112 on the ridge waveguide using photolithography and dry etching processes to obtain a wafer with a lateral grating 110 and a groove 112; subsequently thinning the substrate and then forming an N-type electrode layer 101 on the back side of the substrate layer 102.

[0049] In some implementations, before forming the P-type main electrode 111 and the distributed electrode 109, an insulating layer 108 is deposited on the stacked structure, and then a patterned P-type main electrode injection window and a control electrode injection window are prepared in the insulating layer 108 using photolithography and dry etching processes. Forming the P-type main electrode 111 and the distributed electrode 109 includes: preparing a mask pattern for a lift-off process on the surface of the stacked structure; growing metal electrode material in a metal film evaporation equipment; and then performing a lift-off process to prepare the P-type main electrode 111 and the distributed electrode 109.

[0050] In some implementations, after forming the P-type main electrode 111 and the distributed electrode 109, the substrate is thinned, polished, and cleaned. An N-type electrode layer 101 is sputtered on the back of the substrate layer 102, followed by an annealing process to form a European-style contact. Subsequently, the wafer is cleaved into bar strips, and the bar strips are cleaved into chips.

[0051] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0052] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A semiconductor laser, characterized in that, include: A stacked structure includes a ridge waveguide and sequentially stacked N-type electrode layer, substrate layer, N-type cladding layer, N-type waveguide layer, active layer, and first P-type waveguide layer. The ridge waveguide extends along a first direction on a portion of the top surface of the first P-type waveguide layer. The stacked structure is divided into a laser oscillation region and a beam angle control region arranged in the first direction. The end face of the beam angle control region away from the laser oscillation region is the light output cavity surface. The portion of the ridge waveguide connected to the light output cavity surface has multiple grooves spaced along a second direction. The ridge waveguide between two adjacent grooves serves as a control waveguide. The P-type main electrode is located on the top surface of the ridge waveguide in the laser oscillation region; The distributed electrode includes a plurality of control electrodes arranged at intervals along the second direction, each control electrode corresponding to a control waveguide, and the control electrode being located on the top surface of the corresponding control waveguide. The P-type main electrode is loaded with a corresponding current to enable the laser oscillation region to output the initial laser to the beam angle control region. Each control electrode is loaded with a corresponding control current to enable the beam angle control region to control the beam angle of the initial laser, thereby outputting the target laser from the output cavity surface. Each of the control electrodes is loaded with a corresponding control current to form a controllable carrier distribution. The refractive index of the semiconductor material is related to the carrier distribution to adjust the refractive index of each of the control waveguides. The larger the control current loaded on the control electrode, the higher the refractive index of the corresponding control waveguide.

2. The semiconductor laser according to claim 1, characterized in that, The end face of the laser oscillation region away from the beam angle control region is the rear cavity face; The portion of the ridge waveguide adjacent to the beam angle control region and located in the laser oscillation region has lateral gratings on both sides in the second direction. The P-type main electrode is located on the top surface of the remaining ridge waveguide in the laser oscillation region, excluding the lateral gratings. When the P-type main electrode is loaded with a corresponding current, the rear cavity surface and the lateral grating form a resonant cavity to output the initial laser.

3. The semiconductor laser according to claim 1, characterized in that, The ridge waveguide includes a second P-type waveguide layer and a P-type capping layer. The second P-type waveguide layer is located on a portion of the top surface of the first P-type waveguide layer, and the P-type capping layer is located on the top surface of the second P-type waveguide layer away from the first P-type waveguide layer.

4. The semiconductor laser according to claim 1, characterized in that, The semiconductor laser further includes an insulating layer located on the top surface of the stacked structure, outside the P-type main electrode and the control electrode.

5. The semiconductor laser according to claim 4, characterized in that, The distributed electrode includes N control electrodes, where N is an integer greater than 1; The distributed electrode further includes N leads located on the insulating layer, each lead corresponding to a control electrode, and one end of each lead is connected to the corresponding control electrode. The stacked structure has a first side and a second side arranged in the second direction. Leads corresponding to a portion of the control electrodes adjacent to the first side extend from the corresponding control electrode toward the first side, and leads corresponding to the remaining control electrodes adjacent to the second side extend from the corresponding control electrode toward the second side.

6. The semiconductor laser according to claim 1, characterized in that, The current loaded on the N control electrodes arranged at intervals along the second direction gradually decreases from the middle to both sides, and the beam angle control area focuses the initial laser beam to output the target laser.

7. The semiconductor laser according to claim 1, characterized in that, The current loaded on the N control electrodes arranged at intervals along the second direction gradually decreases from both sides to the middle, and the beam angle control area diverges the initial laser beam to output the target laser.

8. The semiconductor laser according to claim 1, characterized in that, The current loaded on the N control electrodes arranged at intervals along the second direction gradually increases from one side to the other, and the beam angle control area deflects the initial laser beam to output the target laser.

9. A method for fabricating a semiconductor laser, characterized in that, The method for preparing the semiconductor laser according to any one of claims 1 to 8 includes: A stacked structure is formed, the stacked structure including a ridge waveguide and N-type electrode layer, substrate layer, N-type cladding layer, N-type waveguide layer, active layer and first P-type waveguide layer stacked sequentially. The ridge waveguide extends along a first direction on a portion of the top surface of the first P-type waveguide layer. The stacked structure is divided into a laser oscillation region and a beam angle control region arranged in the first direction. The end face of the beam angle control region away from the laser oscillation region is the light output cavity surface. The portion of the ridge waveguide connected to the light output cavity surface has a plurality of grooves arranged at intervals along a second direction. The ridge waveguide between two adjacent grooves serves as a control waveguide. A P-type main electrode is formed, wherein the P-type main electrode is located on the top surface of the ridge waveguide in the laser oscillation region; A distributed electrode is formed, comprising a plurality of control electrodes spaced apart along the second direction, wherein each control electrode corresponds to a control waveguide and is located on the top surface of the corresponding control waveguide.

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