Semiconductor laser and preparation method thereof

Abstract

The embodiment of the invention relates to a semiconductor laser and a preparation method thereof. The semiconductor laser comprises a substrate, a bottom reflector structure, an active layer structure and a top reflector structure, the oxidation groove is formed in the top reflecting mirror structure; the semiconductor laser realizes oxidation of the high-aluminum component material layer in the top reflector structure through the oxidation groove; wherein the top reflecting mirror structure comprises at least one high-aluminum component material layer, and the bottom of the oxidation groove is not in contact with any high-aluminum component material layer. According to the scheme, the problem that the bottom of the oxidation groove is melted can be solved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of semiconductor laser technology, and in particular to a semiconductor laser and a method for manufacturing the same. Background Art

[0002] Currently, semiconductor lasers are widely used in optical communications, 3D sensing, and LiDAR. For example, in vertical-cavity surface-emitting lasers (VCSELs), the shape and size of the photoelectric limiting aperture determine their high-speed performance or far-field divergence angle. This aperture is typically fabricated using a wet oxidation process. The core of this process involves using high-concentration water and oxygen to oxidize the high-aluminum component layer in the laser, creating an insulating aluminum oxide layer with a low refractive index. The final shape of this layer determines the laser's ultimate performance (divergence angle, bandwidth, etc.).

[0003] Before performing the wet oxidation process, the oxidation trench needs to be etched. However, during the etching process, it has been found that some trench etching stops at the top of the high-aluminum layer or in the high-aluminum layer. After the subsequent wet oxidation and passivation layer are produced, burn-through and melting occur in the trench during reliability testing. Summary of the Invention

[0004] Based on this, it is necessary to provide a semiconductor laser and a method for preparing the same in order to address the above technical issues.

[0005] In a first aspect, the present application provides a semiconductor laser comprising a substrate, a bottom reflector structure, an active layer structure, and a top reflector structure; and an oxidation groove, formed in the top reflector structure; The semiconductor laser realizes oxidation of the high aluminum component material layer in the top reflector structure through the oxidation trench; The top reflector structure includes at least one high-aluminum component material layer, and the bottom of the oxidation trench does not contact any of the high-aluminum component material layers.

[0006] In one embodiment, the high aluminum component material layer is Al x Ga （1-x） As material, where 0.95≤x≤1.

[0007] In one embodiment, the top reflector structure includes multiple layers of high-aluminum component material layers, the oxidation groove penetrates part of the high-aluminum component material layers, and the penetrated high-aluminum component material layers are oxidized, and the remaining part of the high-aluminum component material layers that are not penetrated does not contact the bottom of the oxidation groove.

[0008] In one embodiment, there are multiple oxidation grooves, and the high-aluminum component material layer is oxidized through the multiple oxidation grooves to form a light-emitting hole with photoelectric confinement capability.

[0009] In one embodiment, the projection shapes of the oxidation trenches on the substrate are the same, or; A projection shape of at least a portion of the oxidation trenches on the substrate is different from a projection shape of the remaining oxidation trenches on the substrate.

[0010] In one embodiment, the projection of the oxidation trench on the substrate is ring-shaped.

[0011] In one embodiment, it further includes: a passivation layer filled in the oxidation trench; and A metal heat dissipation layer is provided on the passivation layer, and the metal heat dissipation layer is at least located in the oxidation trench.

[0012] In a second aspect, the present application further provides a method for preparing a semiconductor laser, comprising: Providing an epitaxial structure, the epitaxial structure comprising a substrate, a bottom reflector structure, an active layer structure and a top reflector structure; the top reflector structure comprising at least one high aluminum component material layer; preparing a photochromic pattern on the epitaxial structure, and etching the top reflector structure through the photochromic pattern to obtain an oxidation trench; According to the position of each high-aluminum component material layer in the top emitter structure, the oxidation trench is controlled to penetrate at least one of the high-aluminum component material layers and not to contact the other high-aluminum component material layers; and A wet oxidation process is performed on the exposed high aluminum component material layer through the oxidation trench.

[0013] In one embodiment, after the wet oxidation process is completed, the method further comprises: forming a passivation layer on the epitaxial structure; and A metal heat dissipation layer is formed on the passivation layer and is in electrical contact with the top reflector structure; wherein the metal heat dissipation layer is at least filled in the oxidation trench.

[0014] In one embodiment, the high aluminum component material layer is Al x Ga （1-x） As material, where 0.95≤x≤1.

[0015] When etching the oxidation groove, the present application controls the etching depth so that the bottom of the final oxidation groove does not stay in the high-aluminum layer in the top reflector structure. When oxidation is performed accordingly, the high-aluminum layer of the non-oxidized aperture will not be oxidized into aluminum oxide. This avoids the passivation layer at the oxidation groove from contacting with aluminum oxide during the subsequent production of the passivation layer, and instead contacts with the originally planned low-aluminum aluminum gallium arsenide material, thereby improving the problem of melting at the bottom of the groove.

[0016] In a third aspect, the present application further provides a light emitting component, which includes the semiconductor laser described above.

[0017] In a fourth aspect, the present application provides a laser radar, comprising a light transmitting module and a light receiving module, wherein the light transmitting module adopts the light transmitting assembly described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figures 1a-1c A schematic diagram of a portion of the structure of a semiconductor laser in conventional technology; Figure 2 Schematic diagram of the structure of a semiconductor laser in one embodiment of the present application; Figure 3 FIG. 1 is a schematic structural diagram of a semiconductor laser in another embodiment of the present application.

[0019] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0021] It should be understood that the terms "first," "second," and the like used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are used solely to distinguish a first element from another element. For example, a first client may be referred to as a second client, and similarly, a second client may be referred to as a first client, without departing from the scope of this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, features specified as "first" or "second" may explicitly or implicitly include at least one of such features. "Multiple" means at least two, such as two, three, etc., unless otherwise specifically defined. "Several" means at least one, such as one, two, etc., unless otherwise specifically defined.

[0023] Currently, semiconductor lasers are widely used in optical communications, 3D sensing, and LiDAR. For example, in vertical-cavity surface-emitting lasers (VCSELs), the shape and size of the photoelectric limiting aperture determine their high-speed performance or far-field divergence angle. This aperture is typically fabricated using a wet oxidation process. The core of this process involves using high-concentration water and oxygen to oxidize the high-aluminum component layer in the laser, creating an insulating aluminum oxide layer with a low refractive index. The final shape of this layer determines the laser's ultimate performance (divergence angle, bandwidth, etc.).

[0024] Please refer to Figures 1a-1c Before performing the wet oxidation process, the oxidation trenches TH need to be etched. However, during the etching process, it was found that some of the oxidation trenches TH stopped etching on top of the high-aluminum layer or in the high-aluminum layer. After the subsequent wet oxidation and passivation layer 150 was formed, during reliability testing, burn-through and melting occurred in the oxidation trenches TH. The reason for this is that the passivation layer 150 (silicon nitride) at the bottom UD of the oxidation trenches TH was originally in contact with the aluminum gallium arsenide material (low aluminum component). However, since the etching of the oxidation trenches TH stopped above or in the high-aluminum layer 132, this layer was also easily oxidized to aluminum oxide 142 during the wet oxidation. As a result, the passivation layer (silicon nitride) here was in contact with the aluminum oxide 142 instead of the aluminum gallium arsenide material, which led to melting.

[0025] Based on this, Figure 2 As shown, the present application provides a semiconductor laser, including a substrate SUB, a bottom reflector structure 110, an active layer structure 120 and a top reflector structure 130; and An oxidation trench TH is formed in the top reflector structure 130 ; the semiconductor laser oxidizes the high aluminum component material layer in the top reflector structure 130 through the oxidation trench TH to form a photoelectric confinement layer 142 ; The top reflector structure 130 includes at least one high-aluminum component material layer 132 , and the bottom UD of the oxidation trench TH does not contact any of the high-aluminum component material layers 132 .

[0026] Specifically, in one embodiment, the material of the substrate SUB includes but is not limited to GaAs, InP, Si, etc. The bottom reflector structure 110 and the top reflector structure 130 may include a film layer with a periodic change in refractive index to achieve efficient reflection or transmission of light within a specific wavelength range. The film layer with a periodic change in refractive index can be composed of semiconductor materials, dielectric materials, metal-dielectric mixed materials, etc. For example, the bottom reflector structure 110 can be an N-type semiconductor layer, and the top reflector structure 130 can be a P-type semiconductor layer. For another example, the bottom reflector structure 110 can be a P-type semiconductor layer, and the top reflector structure 130 can be an N-type semiconductor layer. Optionally, the material of the N-type semiconductor layer and the P-type semiconductor layer can be but is not limited to GaAs, AlGaAs, etc., which is not limited here. As long as the definition of the resonant cavity can be achieved, it falls within the protection scope of this embodiment.

[0027] Specifically, the bottom reflector structure 110 and the top reflector structure 130 define a resonant cavity structure (not shown), which is the active layer structure 120. The active layer structure 120 includes a resonant cavity, and the resonant cavity is used to generate standing waves. Furthermore, the bottom reflector structure 110 and the top reflector structure 130 define the resonant cavity structure of the semiconductor laser of the present application, that is, the area between the bottom reflector structure 110 and the top reflector structure 130 is the resonant cavity. The resonant cavity is used to generate standing waves. Standing waves are waves formed by two coherent waves propagating in opposite directions on the same straight line and superimposing each other. Specifically, when the two waves are in the same phase, their amplitudes add to form antinodes (i.e., crests). When the two waves are in opposite phases, their amplitudes subtract to form nodes (i.e., troughs). Therefore, the positions of the crests and troughs of the standing wave are fixed.

[0028] A multi-quantum well structure is provided within the active layer structure 120, located at the peak of the resonant cavity. Specifically, the multi-quantum well structure is used to generate stimulated emission of photons. These photons are continuously reflected within the resonant cavity defined by the bottom reflector structure 110 and the top reflector structure 130, where they are continuously enhanced during the reflection process, ultimately emitting laser light at a specific wavelength and with sufficient energy.

[0029] The multi-quantum well structure is where laser gain amplification occurs. The center position of the multi-quantum well structure can be aligned with the position where the light field is strongest (i.e., the peak position of the resonant cavity) to achieve a greater amplification effect. Furthermore, there can be multiple multi-quantum well structures. When multiple multi-quantum well structures are included, the confinement factors of the multi-quantum well structures in the same section of the light field are within the same preset range, that is, the confinement factors of each multi-quantum well structure are maintained at the same level, so that the contribution of each multi-quantum well structure to luminescence is similar. It can be understood that similar luminescence contributions mean that the injection of current into each multi-quantum well structure is more uniform, which helps to reduce the threshold current of the device, thereby reducing the power consumption of the device and extending its service life. Moreover, when the contribution of each multi-quantum well structure to luminescence is similar, the distribution of carriers in each multi-quantum well structure will be more uniform, which helps to reduce carrier recombination losses, thereby improving the overall luminescence efficiency of the device.

[0030] Furthermore, the bottom reflector structure 110 may include a periodically stacked DBR structure, that is, it includes multiple reflectors with an optical thickness of one-quarter the laser wavelength, and the multiple reflectors are arranged alternately according to high and low refractive indices. The top reflector structure 130 also includes a periodically stacked DBR structure, that is, it includes multiple reflectors with an optical thickness of one-quarter the laser wavelength, and the multiple reflectors are arranged alternately according to high and low refractive indices. It can be understood that the components, number of stacking periods, etc. of the DBR structure of the bottom reflector structure 110 and the DBR structure of the top reflector structure 130 may be the same or different, and this embodiment does not limit this. Among them, the material of the top reflector structure 130 and the bottom reflector structure 110 can be a dielectric material with electrical insulation, for example, it can include silicon nitride, silicon oxide, aluminum oxide or titanium oxide. The material of the top reflector structure 130 and the bottom reflector structure 110 can also be a semiconductor material, for example, it can include GaAs and AlGaAs.

[0031] In one embodiment, the high aluminum component material layer 132 may be Al x Ga （1-x） As material, wherein 0.95≤x≤1. Specifically, the value of x can be 0.95, 0.96, 0.97, 0.98, 0.99, or even 1. When x is 1, the high aluminum component layer is AlAs. In other embodiments, the value of x can be further refined to the thousandth, for example, x is 0.952, or 0.955, etc., which will not be further described in this application.

[0032] In one embodiment, the top reflector structure 130 may include multiple layers of high-aluminum component material layers 132, the oxidation trench TH penetrates a portion of the high-aluminum component material layers 132, and the penetrated portion of the high-aluminum component material layers 132 is oxidized to form a photoelectric confinement layer 142, while the remaining portion of the high-aluminum component material layers 132 that is not penetrated does not contact the bottom UD of the oxidation trench TH. By controlling the bottom UD of the oxidation trench TH to not contact the high-aluminum component layer 132, it is prevented from being exposed and oxidized to form aluminum oxide. Common etching processes for the oxidation trench TH include plasma etching (ICP). As is well known, by controlling the time or power of the ICP etching, the oxidation trench TH can be stopped at a desired position.

[0033] The photoelectric confinement layer 142 is disposed adjacent to the active layer structure 120. Specifically, the photoelectric confinement layer 142 is located on the side of the corresponding active layer structure 120 away from the substrate SUB to restrict the flow of current, so that the current flows only within the light-emitting region defined by the photoelectric confinement layer 142, thereby reducing unnecessary energy consumption, thereby reducing the threshold current, and increasing the current density. Furthermore, the photoelectric confinement layer 142 can also confine the light field to the light-emitting region defined by the oxide confinement layer 132, reducing light scattering and diffraction, thereby optimizing the device's divergence angle and improving beam quality. Typically, the oxide confinement layer 132 is disposed at the location with the lowest light field intensity, i.e., at the trough of the standing wave, to provide a smaller confinement factor, thereby helping to reduce the device's divergence angle.

[0034] In one embodiment, the number of the oxidation grooves TH can be multiple, and the high-aluminum component material layer 132 forms a light-emitting hole with photoelectric limitation capability after being oxidized through the multiple oxidation grooves, and the layer where the light-emitting hole is located is the photoelectric limitation layer 142. Furthermore, the projection shape of each of the oxidation grooves TH on the substrate SUB is the same, or; the projection shape of at least part of the oxidation grooves TH on the substrate SUB is different from the projection shape of the remaining oxidation grooves TH on the substrate SUB. In other words, the number and specific shape of the oxidation grooves TH of the present application are not limited, and can be multiple, and the shapes of the multiple oxidation grooves TH can be the same or different. The shape and number of the oxidation grooves TH mainly determine the shape of the final light-emitting hole. This part is not the focus of the description of this application, so it will not be elaborated on.

[0035] In one embodiment, the projection of the oxidation trench TH on the substrate SUB is annular, and the light-emitting hole formed by the annular oxidation trench TH can be circular or elliptical.

[0036] In one embodiment, reference may also be made to Figure 3The semiconductor laser of the present application may further include: a passivation layer 150 filled in the oxidation trench TH; and a metal heat dissipation layer 160 provided on the passivation layer 150, wherein the metal heat dissipation layer 160 is at least located in the oxidation trench TH.

[0037] Specifically, if Figure 3 As shown, the passivation layer 150 is a layer that at least partially insulates the metal heat dissipation layer 160 from one or more other layers or features (e.g., the sidewalls of the trench). Further, the passivation layer 150 can be used to protect the top reflector structure 130. In some embodiments, the passivation layer 150 may include, for example, silicon nitride (SiNX), silicon dioxide (SiO2), a polymer dielectric, or another type of insulating material. In some embodiments, the thickness t of the passivation layer 150 may be in the range of from about 0.92×(λ / nd) to about 1.45×(λ / nd), where λ is the wavelength of the vertical cavity surface emitting laser and nd is the refractive index of the dielectric material. More generally, the thickness T of the passivation layer 150 can be equal to the thickness t plus or minus a value corresponding to the wavelength of the semiconductor laser divided by a multiple of two times the refractive index of the dielectric material (e.g., T = t ± X × λ / (2 * nd), where 0.92 × (λ / nd) ≤ t ≤ 1.45 × (λ / nd), and X is an integer value such as 0, 1, 2, etc.). In some embodiments, the thickness T of the passivation layer 150 can vary by some amount (e.g., ± 10 nm, ± 15 nm) depending on the VCSEL design. Thus, in some embodiments, the thickness of the passivation layer 150 is within a value of approximately 15 nm, which is equal to a value within the range from approximately 0.92 × (λ / nd) to approximately 1.45 × (λ / nd) plus or minus a value equal to X × λ / (2 * nd), where λ is the wavelength of the VCSEL, nd is the refractive index of the dielectric material, and X is an integer value.

[0038] Figure 3 In the embodiment, the semiconductor laser may further include a metal heat dissipation layer 160, which is the top metal layer at the front side of the semiconductor laser. In some embodiments, the metal heat dissipation layer 160 may be a layer in direct contact with the heavily doped P-type electrical contact GaAs layer (for example, through a via penetrating the passivation layer 150), or may be a layer in direct contact with an ohmic contact metal layer (not shown) provided on the heavily doped P-type electrical contact GaAs layer. In some embodiments, the metal heat dissipation layer 160 may serve as an anode for the semiconductor laser. In some embodiments, the metal heat dissipation layer 160 may include an electroplated metal (for example, gold (Au)) and / or a seed metal used in the electroplating process.

[0039] Figure 3In the embodiment, the semiconductor laser may further include a bottom metal 170, which is a bottom metal layer at the back side of the semiconductor laser. In some embodiments, the bottom metal 170 may be a layer that is in electrical contact with the entire surface of the substrate SUB. In some embodiments, the metal heat dissipation layer 160 may serve as a cathode for the semiconductor laser. In some embodiments, the metal heat dissipation layer 160 may include an electroplated metal (e.g., gold (Au)) and / or a seed metal used in the electroplating process.

[0040] Figure 3 In the embodiment, the semiconductor laser may further include a proton implantation region (not shown), which is a region that prevents free carriers from reaching the edge of the trench and / or isolates adjacent semiconductor lasers from each other (for example, if the trench does not completely surround the semiconductor laser). The proton implantation region may include, for example, an ion implantation material, such as a hydrogen / proton implantation material or a similar implantation element, to reduce conductivity.

[0041] Figure 3 The number, arrangement, thickness, order, symmetry, etc. of layers shown are provided as examples. Figure 3 Compared to the layers shown, the semiconductor laser can include additional layers, fewer layers, different layers, differently constructed layers, or differently arranged layers. For example, in some embodiments, the semiconductor laser can include a semiconductor layer (e.g., one or more p-type layers) above the top reflector structure 130 (e.g., instead of the passivation layer 150). As another example, in some embodiments, the semiconductor laser can include an air interface above the top reflector structure 130 (e.g., instead of the passivation layer 150 and the metal heat sink layer 160). Additionally or alternatively, a layer set (e.g., one or more layers) of the semiconductor laser can perform one or more functions described as being performed by another layer set of the semiconductor laser, and any layer can include more than one layer.

[0042] Secondly, you can refer to Figure 2 and Figure 3 , the present application also provides a method for preparing a semiconductor laser, comprising: Providing an epitaxial structure, the epitaxial structure comprising a substrate, a bottom reflector structure, an active layer structure and a top reflector structure; the top reflector structure comprising at least one high aluminum component material layer; preparing a photochromic pattern on the epitaxial structure, and etching the top reflector structure through the photochromic pattern to obtain an oxidation trench; According to the position of each high-aluminum component material layer in the top emitter structure, the oxidation trench is controlled to penetrate at least one of the high-aluminum component material layers and not to contact the other high-aluminum component material layers; and A wet oxidation process is performed on the exposed high aluminum component material layer through the oxidation trench.

[0043] Specifically, the photomodifiable pattern can be, for example, a positive photoresist or a negative photoresist. The shape of the photomodifiable pattern and the oxidation trench TH can be the same or opposite, depending on whether the photoresist is a positive or negative photoresist. Common etching processes for the oxidation trench TH include plasma etching (ICP). As is well known, by controlling the ICP etching time and power, the oxidation trench TH can be stopped at a desired location.

[0044] In one embodiment, after the wet oxidation process is completed, the method further comprises: forming a passivation layer on the epitaxial structure; and A metal heat dissipation layer is formed on the passivation layer and is in electrical contact with the top reflector structure; wherein the metal heat dissipation layer is at least filled in the oxidation trench.

[0045] Specifically, the passivation layer 150 can be formed on the epitaxial structure by, for example, an ALD process or a PECVD or MOCVD process. In addition, a metal heat dissipation layer can be formed by evaporation, sputtering or electroplating. The metal heat dissipation layer is mainly used for electrical interconnection. Since metal has good thermal conductivity, the heat dissipation capacity of the semiconductor laser can be improved by filling a large area of ​​the metal in the oxidation trench TH.

[0046] In one embodiment, the high aluminum component material layer is Al x Ga （1-x） As material, wherein 0.95≤x≤1. Specifically, the value of x can be 0.95, 0.96, 0.97, 0.98, 0.99, or even 1. When x is 1, the high aluminum component layer is AlAs. In other embodiments, the value of x can be further refined to the thousandth, for example, x is 0.952, or 0.955, etc., which will not be further described in this application.

[0047] In summary, when etching the oxidation groove, the present application controls the etching depth so that the bottom of the final oxidation groove does not stay in the high-aluminum layer in the top reflector structure. When oxidation is performed accordingly, the high-aluminum layer of the non-oxidized aperture will not be oxidized into aluminum oxide. This avoids the passivation layer at the oxidation groove from contacting with aluminum oxide during the subsequent production of the passivation layer, and instead contacts with the originally planned low-aluminum aluminum gallium arsenide material, thereby improving the problem of melting at the bottom of the groove.

[0048] In a third aspect, the present application further provides a light emitting assembly, the light emitting assembly comprising the aforementioned semiconductor laser. The light emitting assembly may be a light source in a light emitting module of a laser radar.

[0049] In a fourth aspect, the present application provides a laser radar, comprising a light transmitting module and a light receiving module, wherein the light transmitting module adopts the light transmitting assembly described above.

[0050] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-described embodiments merely represent several implementation methods of the embodiments of the present application. The descriptions thereof are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the concept of the embodiments of the present application, and these all fall within the scope of protection of the embodiments of the present application. Therefore, the scope of protection of the patent of the embodiments of the present application shall be based on the appended claims.

Claims

1. A semiconductor laser, characterized in that comprising a substrate, a bottom reflector structure, an active layer structure and a top reflector structure; as well as an oxidation groove, formed in the top reflector structure; The semiconductor laser realizes oxidation of the high aluminum component material layer in the top reflector structure through the oxidation trench; The top reflector structure includes at least one high-aluminum component material layer, and the bottom of the oxidation trench does not contact any of the high-aluminum component material layers.

2. The semiconductor laser according to claim 1, wherein The high aluminum component material layer is Al x Ga （1-x） As material, where 0.95≤x≤1.

3. The semiconductor laser according to claim 1, wherein The top reflector structure includes multiple layers of high-aluminum component material layers, the oxidation groove penetrates part of the high-aluminum component material layers, and the penetrated high-aluminum component material layers are oxidized, and the remaining part of the high-aluminum component material layers that are not penetrated does not contact the bottom of the oxidation groove.

4. The semiconductor laser according to claim 1, wherein There are multiple oxidation grooves, and the high-aluminum component material layer is oxidized through the multiple oxidation grooves to form a light-emitting hole with photoelectric confinement capability.

5. The semiconductor laser according to claim 4, wherein The projection shapes of the oxidation trenches on the substrate are the same, or; A projection shape of at least a portion of the oxidation trenches on the substrate is different from a projection shape of the remaining oxidation trenches on the substrate.

6. The semiconductor laser according to claim 1, wherein The projection of the oxidation trench on the substrate is ring-shaped.

7. The semiconductor laser according to any one of claims 1 to 6, characterized in that: Also includes: a passivation layer filled in the oxidation trench; as well as A metal heat dissipation layer is provided on the passivation layer, and the metal heat dissipation layer is at least located in the oxidation trench.

8. A method for preparing a semiconductor laser, characterized in that: include: Providing an epitaxial structure, the epitaxial structure comprising a substrate, a bottom reflector structure, an active layer structure, and a top reflector structure; The top reflector structure includes at least one layer of a high aluminum component material; preparing a photochromic pattern on the epitaxial structure, and etching the top reflector structure through the photochromic pattern to obtain an oxidation trench; According to the position of each high-aluminum component material layer in the top emitter structure, the oxidation trench is controlled to penetrate at least one of the high-aluminum component material layers and not to contact the other high-aluminum component material layers; as well as A wet oxidation process is performed on the exposed high aluminum component material layer through the oxidation trench.

9. The method for preparing a semiconductor laser according to claim 8, wherein: After the wet oxidation process is completed, it also includes: forming a passivation layer on the epitaxial structure; and A metal heat dissipation layer is formed on the passivation layer and is in electrical contact with the top reflector structure; wherein the metal heat dissipation layer is at least filled in the oxidation trench.

10. The method for preparing a semiconductor laser according to claim 8, wherein: The high aluminum component material layer is Al x Ga （1-x） As material, where 0.95≤x≤1.

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