Surface-emitting semiconductor laser and preparation method thereof

Abstract

The invention relates to the technical field of semiconductor lasers, in particular to a surface-emitting semiconductor laser which comprises an N-type electrode layer, an N-type substrate layer, an N-type DBR layer, an active layer, an oxidation limiting layer, a P-type DBR layer and a P-type electrode layer which are sequentially stacked. Wherein the oxidation limiting layer is provided with a large oxidation hole and a small oxidation hole, the orthographic projection area of the large oxidation hole on the N-type substrate layer is larger than the orthographic projection area of the small oxidation hole on the N-type substrate layer, and the P-type electrode layer is right opposite to the large oxidation hole. The invention is at least beneficial to improving the performance of the surface-emitting semiconductor laser.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor lasers, and particularly relates to a surface-emitting semiconductor laser and a preparation method thereof. Background Art

[0002] Since the invention of surface-emitting lasers, with their characteristics such as circularly symmetric light spots, low threshold currents, easy implementation of two-dimensional integration, high coupling efficiency, and excellent beam quality, they have been widely used in fields such as three-dimensional sensing, 3D printing, driverless, laser display, optical communication, and optical interconnection. With the continuous growth of the application demand for vertical-cavity surface-emitting lasers in fields such as optical communication and optical sensing, it has become an urgent task to study vertical-cavity surface-emitting lasers with high beam quality, single-mode output, and high power.

[0003] Currently, vertical-cavity surface-emitting lasers that achieve single-mode operation usually limit the number of modes by reducing the aperture of the oxidation holes. The structures of vertical-cavity surface-emitting lasers that achieve single-mode output under the condition of a large oxidation hole aperture mainly include surface relief structures, photonic crystal structures, and surface grating structures, etc. These methods achieve single-mode output by introducing losses to higher-order modes. However, since these structures only perform shallow etching on the cavity surface, higher-order modes can still effectively resonate in the cavity. Therefore, their loss effect is limited, especially at large currents, higher-order modes may still be excited. Summary of the Invention

[0004] In view of this, the present invention aims to provide a surface-emitting semiconductor laser and a preparation method thereof, which are at least beneficial to improving the performance of the surface-emitting semiconductor laser.

[0005] To achieve the above object, the technical solution of the present invention is realized as follows:

[0006] On the one hand, the present invention provides a surface-emitting semiconductor laser, including: an N-type electrode layer, an N-type substrate layer, an N-type DBR layer, an active layer, an oxidation confinement layer, a P-type DBR layer, and a P-type electrode layer that are sequentially stacked; wherein, the oxidation confinement layer has large oxidation holes and small oxidation holes, the area of the orthographic projection of the large oxidation holes on the N-type substrate layer is larger than the area of the orthographic projection of the small oxidation holes on the N-type substrate layer, and the P-type electrode layer is aligned with the large oxidation holes.

[0007] Further, the distance between the large oxidation holes and the small oxidation holes is not greater than 0.8 μm.

[0008] Further, the ratio of the area of the orthographic projection of the large oxidation holes on the N-type substrate layer to the area of the orthographic projection of the small oxidation holes on the N-type substrate layer is in the range of 1.6 - 2.

[0009] Further, the number of the small oxidation holes is 1.

[0010] Further, the shape of the small oxidation holes is circular.

[0011] Further, the thickness of the oxidation confinement layer is in the range of 50 nm to 1000 nm.

[0012] Further, the orthographic projection of the large oxidation holes on the N-type substrate layer is circular, and the aperture diameter of the large oxidation holes is in the range of 5 μm to 15 μm.

[0013] Further, the orthographic projection of the P-type electrode layer on the N-type substrate layer coincides with the orthographic projection of the large oxidation holes on the N-type substrate layer, or the orthographic projection of the P-type electrode layer on the N-type substrate layer is located within the orthographic projection of the large oxidation holes on the N-type substrate layer.

[0014] On the other hand, the present invention provides a method for manufacturing a surface-emitting semiconductor laser, including: forming an N-type substrate layer, an N-type DBR layer, an active layer, an initial oxidation confinement layer, and a P-type DBR layer stacked in sequence; performing side oxidation on the initial oxidation confinement layer to form large oxidation holes and small oxidation holes in the initial oxidation confinement layer, wherein the orthographic projection area of the large oxidation holes on the N-type substrate layer is larger than the orthographic projection area of the small oxidation holes on the N-type substrate layer; forming an N-type electrode layer on the surface of the N-type substrate layer away from the N-type DBR layer, and forming a P-type electrode layer on the surface of the P-type DBR layer away from the N-type DBR layer, and the P-type electrode layer is opposite to the large oxidation holes.

[0015] Compared with the prior art, the present invention can achieve the following beneficial effects: The surface-emitting semiconductor laser provided by the present invention realizes fundamental transverse mode output through the combined design of large oxidation holes and small oxidation holes. By optimizing the size and spacing of the large oxidation holes and small oxidation holes, high-order modes are coupled into the small oxidation holes and effectively suppressed, while the fundamental mode is concentrated in the large oxidation holes and stably propagates. This design not only improves the single-mode stability of the surface-emitting semiconductor laser, but also significantly improves the beam quality, providing a new technical path for the research of high-performance lasers. Specifically, the oxidation holes in the oxidation confinement layer of the surface-emitting semiconductor laser provided by the present invention include large oxidation holes and small oxidation holes beside them, enabling the fundamental mode to be distributed in the large oxidation holes, while part of the high-order modes are coupled into the small oxidation holes, and only current is injected into the large oxidation holes, which can not only significantly improve the single-mode stability, but also greatly enhance the beam output quality, effectively improving the performance of the surface-emitting semiconductor laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0017] Figure 1Schematic structural diagram of the surface-emitting semiconductor laser according to the embodiment of the present invention;

[0018] Figure 2 Top view of the oxidation confinement layer according to the embodiment of the present invention;

[0019] Figure 3 Schematic diagram of the laser mode distribution of the surface-emitting semiconductor laser provided by the embodiment of the present invention and the schematic diagram of the laser mode distribution of the surface-emitting semiconductor laser provided by the comparative example.

[0020] Description of reference numerals: 110, N-type electrode layer; 109, N-type substrate layer; 107, N-type DBR layer; 106, active layer; 200, oxidation confinement layer; 102, P-type DBR layer; 101, P-type electrode layer; 201, large oxidation hole; 202, small oxidation hole; 108, transition layer; 103, insulating layer. Detailed implementation manners

[0021] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present 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 only used to explain the present invention, rather than limiting the present invention.

[0022] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0023] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0024] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0025] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0026] Reference Figure 1 and Figure 2 On the one hand, the present invention provides a surface-emitting semiconductor laser, including: an N-type electrode layer 110, an N-type substrate layer 109, an N-type DBR layer 107, an active layer 106, an oxidation confinement layer 200, a P-type DBR layer 102, and a P-type electrode layer 101 that are sequentially stacked; wherein, the oxidation confinement layer 200 has large oxidation holes 201 and small oxidation holes 202, the area of the orthographic projection of the large oxidation holes 201 on the N-type substrate layer 109 is larger than the area of the orthographic projection of the small oxidation holes 202 on the N-type substrate layer 109, and the P-type electrode layer 101 is directly opposite to the large oxidation holes 201. That is to say, current is only injected into the large oxidation holes 201. Among them, the function of the small oxidation holes 202 is to provide strong coupling loss for high-order modes. When high-order modes attempt to propagate in the structure, their energy is effectively coupled to the small oxidation holes 202 and gradually attenuates due to optical loss during propagation. In this way, the existence of high-order modes can be effectively suppressed, making the fundamental mode the main output mode, thereby improving the performance and beam quality of the surface-emitting semiconductor laser.

[0027] Reference Figure 3 , Figure 3 (a) and (b) in Figure 3 show two possible laser mode distribution states of the comparative example with only large oxidation holes,

[0028] (c) and (d) in

[0029] show the laser mode distribution states when small oxidation holes are provided in the large oxidation holes. It can be clearly seen that the small oxidation holes have the process of coupling the fundamental mode of the large oxidation holes. The small oxidation holes can separate the fundamental mode with poor efficiency in the original large oxidation holes into the small oxidation holes. In this way, the small oxidation holes are also the fundamental mode, and the utilization of the fundamental mode of the large oxidation holes is beneficial to improving the luminous efficiency.

[0028] It should be noted that since the high-order modes are coupled by the small oxidation holes 202, only current needs to be injected into the large oxidation holes 201, which is beneficial to improving the single-mode stability of the surface-emitting semiconductor laser.

[0029] It is understandable that traditional surface-emitting semiconductor laser structures generally support multiple modes to work together. A common method to achieve single-mode output is to reduce the aperture of the oxidation hole. However, reducing the aperture of the oxidation hole is often accompanied by a series of problems. Reducing the size of the oxidation hole means that the mode confinement ability of the laser is enhanced, but at the same time, it may also lead to a decrease in the output power of the laser. Reducing the oxidation hole may limit the optical output mode of the laser, resulting in the inability to fully release the power, thus affecting its efficiency and application performance. Reducing the oxidation hole usually also increases the thermal resistance. A smaller aperture means that heat is difficult to effectively dissipate from the laser, which may cause the device to overheat, thus affecting its performance and stability. Therefore, although reducing the aperture of the oxidation hole helps to support single-mode operation, if not properly handled, it may lead to incomplete suppression of higher-order modes, resulting in mode competition or mode instability, affecting the performance of the laser. Therefore, in the present invention, by designing a small oxidation hole 202 beside the large oxidation hole 201, the coupling of the higher-order mode with the small oxidation hole 202 is achieved, while the fundamental mode is concentrated in the large oxidation hole 201, and current is only injected into the large oxidation hole 201, greatly improving the stability of single-mode output.

[0030] In some embodiments, stable single-mode output and excellent beam quality can be achieved by precisely controlling the distance between the large oxidation hole 201 and the small oxidation hole 202.

[0031] Furthermore, the distance between the large oxidation hole 201 and the small oxidation hole 202 is not greater than 0.8 μm. A smaller distance helps to more precisely control the mode output of the laser. Especially for single-mode operation, a smaller distance can better confine the transverse distribution of the laser mode, ensuring the preferential excitation of the fundamental mode. Reducing the distance between the large oxidation hole and the small oxidation hole helps to reduce the loss during light propagation, enabling the light beam to pass through each part of the laser more effectively. This optimized design can improve the output power, especially while increasing the power density, and avoid excessive light scattering.

[0032] It should be noted that the oxidation confinement layer 200 includes a non-oxidized layer and an oxidized layer. The non-oxidized layer is the oxidation hole. In the embodiments of the present invention, the oxidation hole includes a large oxidation hole 201 and a small oxidation hole 202. The injection region of carriers is restricted by the large oxidation hole 201, and the oxidized layer can be formed by wet-side oxidation technology.

[0033] In some embodiments, the surface-emitting semiconductor laser further includes a transition layer 108. The transition layer 108 is located on the upper and lower surfaces of the active layer 106, that is, there is a transition layer 108 between the active layer 106 and the oxidation confinement layer 200, and there is also a transition layer 108 between the active layer 106 and the N-type DBR layer 107.

[0034] In some embodiments, the cavity length of the surface-emitting semiconductor laser is in the range of 3 μm to 10 μm. The cavity length is the distance from the gain region to the mirrors at both ends of the laser, which determines the propagation path length of light in the cavity and thus affects the optical characteristics of the laser, such as mode selectivity, output power, and laser stability.

[0035] In some embodiments, the surface-emitting semiconductor laser has a mesa structure located above the active layer 106. The oxidation confinement layer 200 and the P-type DBR layer 102 form the mesa structure, which can be a cylindrical mesa structure, and the diameter of the mesa structure can be in the range of 10 μm to 50 μm.

[0036] Furthermore, the ratio of the orthographic projection area of the large oxidation hole 201 on the N-type substrate layer 109 to the orthographic projection area of the small oxidation hole 202 on the N-type substrate layer 109 is in the range of 1.6 to 2. It can be understood that the specific sizes of the large oxidation hole 201 and the small oxidation hole 202 can be set according to the characteristics of the surface-emitting semiconductor laser.

[0037] Preferably, the ratio of the orthographic projection area of the large oxidation hole 201 on the N-type substrate layer 109 to the orthographic projection area of the small oxidation hole 202 on the N-type substrate layer 109 is in the range of 1.6 to 2, and the distance between the large oxidation hole 201 and the small oxidation hole 202 is between 0.5 and 0.8 μm. Under such design parameters, the first-order mode can be effectively coupled into the small oxidation hole and converted into the fundamental mode, which helps to improve the working efficiency of the optical device. By coupling the first-order mode, unnecessary mode losses and energy losses can be reduced, thereby enhancing the performance and stability of the device. In addition, by optimizing the size of the small oxidation hole and its distance from the large oxidation hole, the coupling efficiency and mode conversion characteristics can be flexibly adjusted within a certain range, thus providing more design freedoms to meet different application requirements.

[0038] Furthermore, the number of small oxidation holes 202 is 1. Usually, a single small oxidation hole has a high beam quality and can effectively control the laser mode, avoiding complex phenomena such as mode coupling. If the number of small oxidation holes is multiple, it not only increases the structural complexity and manufacturing difficulty but also more easily induces the coupling of the second-order mode because multiple oxidation holes may cause more mode cross-couplings, leading to more complex mode competition, especially in multimode lasers. Generally speaking, a single small oxidation hole structure is suitable for occasions that require good mode control and a simpler design, while multiple small oxidation hole structures require more precise designs to avoid unnecessary mode coupling problems.

[0039] Furthermore, the shape of the small oxidation holes 202 is circular or rectangular, preferably circular. Circular small oxidation holes have better symmetry, which enables more uniform propagation of the mode. The light beam will not be affected by irregular edges, thus improving the coupling efficiency of the optical mode, especially for the coupling of the fundamental mode. Circular holes have no corners and edges, and the propagation of light in the holes is more stable. Especially during the conversion of high-order modes to the fundamental mode, circular holes can provide better efficiency. When the shape of the small oxidation hole is square, its symmetry is poor, which may limit the propagation direction of the optical mode to a certain extent, thereby affecting the uniformity and coupling efficiency of the mode. Especially in the coupling of high-order modes, the boundary of the square hole will affect the propagation of the mode, resulting in uneven energy distribution. Moreover, the manufacturing of small oxidation holes of other shapes may be more complex than that of circular holes, requiring precise control of the details of the corners and edges, which increases the processing difficulty and cost.

[0040] Furthermore, the thickness of the oxidation confinement layer 200 is in the range of 50 nm to 1000 nm.

[0041] Furthermore, the orthographic projection of the large oxidation hole 201 on the N-type substrate layer 109 is circular, and the aperture of the large oxidation hole 201 is in the range of 5 μm to 15 μm. It should be noted that the aperture of the large oxidation hole 201 provided by the present invention is larger than the oxidation aperture of traditional vertical cavity surface emitting lasers. Thus, the large oxidation hole can accommodate more light, enhancing the confinement of the light beam. By increasing the aperture of the large oxidation hole, the laser can obtain more output optical power, thereby improving the overall output performance. In the double oxidation hole structure, the design of the large oxidation hole can enhance the transverse mode control of the laser. Especially for lasers that require single-mode output, and the large oxidation hole supports higher current injection and can adapt to a higher current density, especially in high-power lasers. The large oxidation hole can also distribute the current more evenly, reducing the non-uniformity of the current density. In the double oxidation hole structure provided by the present invention, by reasonably designing the ratio of the large oxidation hole to the small oxidation hole, a better balance can be achieved in terms of the power, stability, and thermal management of the laser.

[0042] Furthermore, the positive projection of the P-type electrode layer 101 on the N-type substrate layer 109 coincides with the positive projection of the large oxidation hole 201 on the N-type substrate layer 109, or the positive projection of the P-type electrode layer 101 on the N-type substrate layer 109 is located within the positive projection of the large oxidation hole 201 on the N-type substrate layer 109. In this way, it can be ensured that current can be uniformly injected into the gain region of the laser, and the current can be evenly distributed from the electrode to the region of the oxidation hole, avoiding too high current density or uneven regions, reducing heat accumulation caused by current concentration, and avoiding the P-type electrode layer from affecting the optical mode distribution in the large oxidation hole region, thus ensuring the stability of laser output and the beam quality. On this basis, the specific shape of the P-type electrode layer 101 can be appropriately changed according to the requirements of carrier injection, and the present invention does not limit the specific shape of the P-type electrode layer 101.

[0043] It should be noted that the material and component design of each film layer in the surface-emitting semiconductor laser provided by the present invention can be the same as the film layer material and component design of the currently widely used and mature vertical-cavity surface-emitting laser.

[0044] A specific embodiment of the present invention is provided below. In this embodiment, the surface-emitting semiconductor laser is a structure based on an aluminum gallium arsenide material system, specifically as follows:

[0045] The surface-emitting semiconductor laser includes an N-type electrode layer 110, an N-type substrate layer 109, an N-type DBR layer 107, an active layer 106, a transition layer 108, an oxidation confinement layer 200, a P-type DBR layer 102, a P-type electrode layer 101, and an insulating layer 103.

[0046] In some examples, the N-type substrate layer 109 is made of N-type GaAs material, the N-type DBR layer 107 includes AlGaAs material, the component of Al in the N-type DBR layer 107 can be in the range of 0.1 to 0.9, the N-type DBR layer 107 can be doped with Si, the thickness of the N-type DBR layer 107 can be in the range of 0.5 μm to 10 μm, and the doping concentration of Si can be in the range of 1E16 / cm 3 ~5E18 / cm 3 range.

[0047] In some examples, the material of the transition layer 108 includes AlGaAs, wherein the component of Al can be in the range of 0.2 to 0.7, and the transition layer 108 is a non-intentionally doped layer.

[0048] In some examples, the active layer 106 is an unintentionally doped layer. Specifically, the active layer 106 has a barrier / quantum well / barrier structure. The material of the barrier can be AlGaAs, the material of the quantum well can be GaAs, the Al composition can be in the range of 0.1 to 0.5, the thickness of the barrier can be in the range of 1 nm to 30 nm, the thickness of the quantum well can be in the range of 1 nm to 20 nm, and the emission wavelength band of the surface-emitting semiconductor laser can be in the range of 600 nm to 1200 nm. Within this wavelength band range, the laser can stably emit light of a specific wavelength. The specific wavelength value depends on the material, thickness, and composition of the quantum well, as well as the material and thickness of the barrier.

[0049] In some examples, the material of the non-oxidized layer corresponding to the large oxidation hole 201 includes AlGaAs, where the Al composition is in the range of 0.9 to 0.99. C can be doped in the non-oxidized layer corresponding to the large oxidation hole 201. The thickness of the non-oxidized layer corresponding to the large oxidation hole 201 can be in the range of 50 nm to 1000 nm, and the doping concentration of C can be in the range of 1E16 / cm 3 ~1E19 / cm 3 range.

[0050] In some examples, the material of the non-oxidized layer corresponding to the small oxidation hole 202 includes AlGaAs, where the Al composition is in the range of 0.9 to 0.99. C can be doped in the non-oxidized layer corresponding to the small oxidation hole 202. The thickness of the non-oxidized layer corresponding to the small oxidation hole 202 can be in the range of 50 nm to 1000 nm, and the doping concentration of C can be in the range of 1E16 / cm 3 ~1E19 / cm 3 range.

[0051] In some examples, the material of the P-type DBR layer 102 includes AlGaAs, where the Al composition can be in the range of 0.1 to 0.9. The dopant of the P-type DBR layer 102 can be C. The thickness of the P-type DBR layer 102 can be in the range of 0.5 μm to 6 μm, and the doping concentration of the dopant can be in the range of 1E16 / cm 3 ~1E19 / cm 3 range.

[0052] In some examples, the thickness of the N-type electrode layer 110 can be in the range of 200 nm to 500 nm. The material of the N-type electrode layer 110 includes an alloy formed by at least one or more of metals titanium, platinum, gold, nickel, and germanium.

[0053] In some examples, the material of the oxide layer in the oxidation confinement layer 200 can include aluminum oxide, and the thickness of the oxide layer can be in the range of 50 nm to 1000 nm.

[0054] In some examples, the material of the insulating layer 103 includes at least one of silicon oxide, silicon nitride, or silicon oxynitride, and the thickness of the insulating layer 103 can be in the range of 50 nm to 1000 nm.

[0055] On the other hand, the present invention provides a method for manufacturing a surface-emitting semiconductor laser for forming the surface-emitting semiconductor laser provided in the above embodiments. The manufacturing method includes: forming an N-type substrate layer 109, an N-type DBR layer 107, an active layer 106, an initial oxidation confinement layer 200, and a P-type DBR layer 102 stacked in sequence; performing side oxidation on the initial oxidation confinement layer 200 to form a large oxidation hole 201 and a small oxidation hole 202 in the initial oxidation confinement layer 200, wherein the area of the orthographic projection of the large oxidation hole 201 on the N-type substrate layer 109 is larger than the area of the orthographic projection of the small oxidation hole 202 on the N-type substrate layer 109; forming an N-type electrode layer 110 on the surface of the N-type substrate layer 109 away from the N-type DBR layer 107, and forming a P-type electrode layer 101 on the surface of the P-type DBR layer 102 away from the N-type DBR layer 107, and the P-type electrode layer 101 is aligned with the large oxidation hole 201.

[0056] Further, the step of performing side oxidation on the initial oxidation confinement layer 200 to form a large oxidation hole 201 and a small oxidation hole 202 includes: using oxygen and water vapor as the oxidation atmosphere and performing oxidation in a wet oxidation furnace. The temperature control during the oxidation process is one of the key factors determining the pore size. First, oxidation can be carried out for a longer time to form initial oxidation holes in the mesa structure. At this time, the oxidation rate is higher and the oxidation time is longer to ensure the formation of the initial oxidation holes. After the initial oxidation holes are formed, the local temperature or oxidation time is adjusted to form large and small oxidation holes. Specifically, by controlling the temperature gradient of the oxidation region, the oxidation rate around the initial oxidation holes for forming large oxidation holes can be slowed down, and the oxidation rate around the initial oxidation holes for forming small oxidation holes can be accelerated or remain unchanged, so that small oxidation holes are formed beside the large oxidation holes. In some examples, the oxidation time of the small oxidation holes is shorter than that of the large oxidation holes, and the oxidation temperature of the small oxidation holes can be slightly higher than that of the large oxidation holes to ensure that oxidation occurs in the area beside the large oxidation holes without overly affecting the structure of the large oxidation holes. By precisely controlling the oxidation time, temperature, and atmosphere, the size difference between the large oxidation holes and the small oxidation holes can be ensured. The large oxidation holes usually have a longer oxidation time and a higher temperature, resulting in a larger pore size, while the small oxidation holes are formed through a shorter oxidation time or local adjustment. Finally, through means such as microscopic examination and scanning electron microscopy, the size, shape, and position of the large oxidation holes and the small oxidation holes are accurately measured to ensure that they meet the design specifications.

[0057] The following provides a specific implementation method for manufacturing a surface-emitting semiconductor laser, and the specific steps are as follows:

[0058] Step 1: Design a first photomask for etching to form a mesa structure, and design a second photomask for etching to form a P-type electrode;

[0059] Step 2: Select an N-type GaAs substrate, and sequentially deposit an N-type DBR layer 107, a transition layer 108, an active layer 106, a transition layer 108, an initial oxidation confinement layer 200, and a P-type DBR layer 102 on the selected N-type GaAs substrate;

[0060] Step 3: Use the first photomask to form a mask layer with an etching window on the top surface of the P-type DBR layer 102 by photolithography, use a dry etching process to etch to form a mesa structure, use a buffered oxide etchant to remove the mask layer, and clean;

[0061] Step 4: Through a wet oxidation process, laterally oxidize the initial oxidation confinement layer 200 in the mesa structure to form an oxidation layer with a high aluminum component, and form a large oxidation hole 201. Adjust the oxidation conditions to form a small oxidation hole 202 beside the large oxidation hole 201;

[0062] Step 5: Use plasma-enhanced chemical vapor deposition to grow an insulating layer 103, and clean to ensure no pollution in subsequent processes;

[0063] Step 6: Use the second photomask to form a photoresist layer with an etching window on the insulating layer 103, and perform dry etching on the insulating layer 103 to define the position of the P-type electrode;

[0064] Step 7: Use a metal film evaporation device to grow a P-type electrode layer 101 on the wafer surface;

[0065] Step 8: Thin the N-type GaAs substrate to obtain an N-type substrate layer 109, which can be thinned to 100 μm to 300 μm. After polishing and cleaning, ensure that the substrate thickness meets the requirements. Sputter an N-type electrode layer 110 on the N-type substrate layer 109, and perform an annealing process on the wafer to make the N-type electrode layer 110 form a good ohmic contact with the N-type substrate layer 109.

[0066] The surface-emitting semiconductor laser and its manufacturing method provided by the above embodiments design and optimize oxidation conditions beside a large oxidation hole 201 to generate a small oxidation hole 202, realizing partial coupling of high-order modes to enhance mode loss, thereby effectively suppressing the existence of high-order modes. This design enables the fundamental mode to be stably distributed inside the large oxidation hole 201. By injecting current only into the large oxidation hole 201, not only the stability of single-mode output is improved, but also the beam quality of the laser is significantly optimized. This structure solves the problems in the prior art such as limited shallow etching loss and easy excitation of high-order modes under high current, providing a new technical solution for application fields with high demands for high-quality beams and single-mode high power, such as optical communication and optical sensing.

[0067] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in the disclosure of the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and no limitation is imposed herein.

[0068] The above specific embodiments do not constitute a limitation to the protection scope of the present 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 the present invention shall be included within the protection scope of the present invention.

Claims

1. A surface emitting semiconductor laser, characterized in that: include: An N-type electrode layer, an N-type substrate layer, an N-type DBR layer, an active layer, an oxidation restriction layer, a P-type DBR layer and a P-type electrode layer are sequentially stacked; The oxidation restriction layer has large oxidation holes and small oxidation holes, the orthographic projection area of ​​the large oxidation holes on the N-type substrate layer is larger than the orthographic projection area of ​​the small oxidation holes on the N-type substrate layer, and the P-type electrode layer is directly opposite to the large oxidation holes.

2. The surface emitting semiconductor laser according to claim 1, characterized in that The distance between the large oxidation pores and the small oxidation pores is no greater than 0.8 μm.

3. The surface emitting semiconductor laser according to claim 1, characterized in that The ratio of the orthographic projection area of ​​the large oxide hole on the N-type substrate layer to the orthographic projection area of ​​the small oxide hole on the N-type substrate layer is in the range of 1.6 to 2.

4. The surface emitting semiconductor laser according to claim 1, characterized in that The number of the small oxidation pore is 1.

5. The surface emitting semiconductor laser according to claim 1, characterized in that The small oxidation pores are circular in shape.

6. The surface emitting semiconductor laser according to claim 1, characterized in that The thickness of the oxidation restriction layer is in the range of 50 nm to 1000 nm.

7. The surface emitting semiconductor laser according to claim 1, characterized in that The orthographic projection of the large oxide hole on the N-type substrate layer is circular, and the aperture of the large oxide hole is in the range of 5 μm to 15 μm.

8. The surface emitting semiconductor laser according to claim 1, characterized in that The orthographic projection of the P-type electrode layer on the N-type substrate layer coincides with the orthographic projection of the large oxide hole on the N-type substrate layer, or the orthographic projection of the P-type electrode layer on the N-type substrate layer is located within the orthographic projection of the large oxide hole on the N-type substrate layer.

9. A method for preparing a surface-emitting semiconductor laser, characterized in that: include: An N-type substrate layer, an N-type DBR layer, an active layer, an initial oxidation restriction layer, and a P-type DBR layer are sequentially stacked; Performing side oxidation on the initial oxidation limiting layer to form large oxidation holes and small oxidation holes in the initial oxidation limiting layer, wherein the orthographic projection area of ​​the large oxidation holes on the N-type substrate layer is larger than the orthographic projection area of ​​the small oxidation holes on the N-type substrate layer; An N-type electrode layer is formed on a surface of the N-type substrate layer away from the N-type DBR layer, and a P-type electrode layer is formed on a surface of the P-type DBR layer away from the N-type DBR layer, wherein the P-type electrode layer faces the large oxide hole.

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